From fae1585729ded06eb826576b1d9a318b62d816ed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Knut=20Olav=20L=C3=B8ite?= <koloite@gmail.com>
Date: Tue, 17 Sep 2024 14:59:20 +0200
Subject: [PATCH 1/2] test: ignore if the mock server failed to return a row
 (#3335)

The test uses a trick in the mock server, where the mock server is
requested to freeze after returning the first row. However, when the
mock server adds the first row to the stream, it is not guaranteed to be
readable for the client, which again causes the test to hang on the
ResultSet#next() call. The gRPC libraries then execute keep-alive
requests to keep the TCP connection alive while waiting for data from
the mock server, which will never come. This caused the query to
eventually fail with a RESOURCE_EXHAUSTED error.

The tests work around this issue by just ignoring the case when the mock
server fails to return the first row, as it is something that only very
sporadically happens.
---
 .../cloud/spanner/v1/SpannerClient.java       |   4 +
 .../cloud/spanner/v1/SpannerSettings.java     |  17 +-
 .../spanner/v1/stub/SpannerStubSettings.java  |  21 +-
 .../reflect-config.json                       |  36 +
 .../CloseSpannerWithOpenResultSetTest.java    |  28 +-
 .../spanner/v1/SpannerClientHttpJsonTest.java |   6 +
 .../cloud/spanner/v1/SpannerClientTest.java   |   8 +
 .../spanner/v1/BeginTransactionRequest.java   | 317 +++++++++
 .../v1/BeginTransactionRequestOrBuilder.java  |  47 ++
 .../com/google/spanner/v1/CommitRequest.java  | 335 +++++++++
 .../spanner/v1/CommitRequestOrBuilder.java    |  50 ++
 .../com/google/spanner/v1/CommitResponse.java | 396 +++++++++++
 .../spanner/v1/CommitResponseOrBuilder.java   |  40 ++
 .../spanner/v1/CommitResponseProto.java       |  28 +-
 .../spanner/v1/ExecuteBatchDmlResponse.java   | 347 ++++++++++
 .../v1/ExecuteBatchDmlResponseOrBuilder.java  |  53 ++
 .../v1/MultiplexedSessionPrecommitToken.java  | 648 ++++++++++++++++++
 ...iplexedSessionPrecommitTokenOrBuilder.java |  54 ++
 .../google/spanner/v1/PartialResultSet.java   | 347 ++++++++++
 .../spanner/v1/PartialResultSetOrBuilder.java |  53 ++
 .../java/com/google/spanner/v1/ResultSet.java | 351 +++++++++-
 .../google/spanner/v1/ResultSetOrBuilder.java |  57 +-
 .../com/google/spanner/v1/ResultSetProto.java |  74 +-
 .../com/google/spanner/v1/SpannerProto.java   | 334 ++++-----
 .../com/google/spanner/v1/Transaction.java    | 351 +++++++++-
 .../google/spanner/v1/TransactionOptions.java | 143 +++-
 .../spanner/v1/TransactionOrBuilder.java      |  57 +-
 .../google/spanner/v1/TransactionProto.java   |  95 ++-
 .../google/spanner/v1/commit_response.proto   |  10 +
 .../proto/google/spanner/v1/result_set.proto  |  19 +
 .../proto/google/spanner/v1/spanner.proto     |  25 +
 .../proto/google/spanner/v1/transaction.proto |  30 +
 32 files changed, 4121 insertions(+), 260 deletions(-)
 create mode 100644 proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitToken.java
 create mode 100644 proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitTokenOrBuilder.java

diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java
index 64ffdb0902a..8625c17785a 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerClient.java
@@ -1629,6 +1629,7 @@ public final Transaction beginTransaction(String session, TransactionOptions opt
    *               SessionName.of("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]").toString())
    *           .setOptions(TransactionOptions.newBuilder().build())
    *           .setRequestOptions(RequestOptions.newBuilder().build())
+   *           .setMutationKey(Mutation.newBuilder().build())
    *           .build();
    *   Transaction response = spannerClient.beginTransaction(request);
    * }
@@ -1662,6 +1663,7 @@ public final Transaction beginTransaction(BeginTransactionRequest request) {
    *               SessionName.of("[PROJECT]", "[INSTANCE]", "[DATABASE]", "[SESSION]").toString())
    *           .setOptions(TransactionOptions.newBuilder().build())
    *           .setRequestOptions(RequestOptions.newBuilder().build())
+   *           .setMutationKey(Mutation.newBuilder().build())
    *           .build();
    *   ApiFuture<Transaction> future = spannerClient.beginTransactionCallable().futureCall(request);
    *   // Do something.
@@ -1911,6 +1913,7 @@ public final CommitResponse commit(
    *           .setReturnCommitStats(true)
    *           .setMaxCommitDelay(Duration.newBuilder().build())
    *           .setRequestOptions(RequestOptions.newBuilder().build())
+   *           .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
    *           .build();
    *   CommitResponse response = spannerClient.commit(request);
    * }
@@ -1955,6 +1958,7 @@ public final CommitResponse commit(CommitRequest request) {
    *           .setReturnCommitStats(true)
    *           .setMaxCommitDelay(Duration.newBuilder().build())
    *           .setRequestOptions(RequestOptions.newBuilder().build())
+   *           .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
    *           .build();
    *   ApiFuture<CommitResponse> future = spannerClient.commitCallable().futureCall(request);
    *   // Do something.
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerSettings.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerSettings.java
index a785ff6d993..721e874e01e 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerSettings.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/SpannerSettings.java
@@ -76,7 +76,9 @@
  * <p>The builder of this class is recursive, so contained classes are themselves builders. When
  * build() is called, the tree of builders is called to create the complete settings object.
  *
- * <p>For example, to set the total timeout of createSession to 30 seconds:
+ * <p>For example, to set the
+ * [RetrySettings](https://cloud.google.com/java/docs/reference/gax/latest/com.google.api.gax.retrying.RetrySettings)
+ * of createSession:
  *
  * <pre>{@code
  * // This snippet has been automatically generated and should be regarded as a code template only.
@@ -92,10 +94,21 @@
  *             .createSessionSettings()
  *             .getRetrySettings()
  *             .toBuilder()
- *             .setTotalTimeout(Duration.ofSeconds(30))
+ *             .setInitialRetryDelayDuration(Duration.ofSeconds(1))
+ *             .setInitialRpcTimeoutDuration(Duration.ofSeconds(5))
+ *             .setMaxAttempts(5)
+ *             .setMaxRetryDelayDuration(Duration.ofSeconds(30))
+ *             .setMaxRpcTimeoutDuration(Duration.ofSeconds(60))
+ *             .setRetryDelayMultiplier(1.3)
+ *             .setRpcTimeoutMultiplier(1.5)
+ *             .setTotalTimeoutDuration(Duration.ofSeconds(300))
  *             .build());
  * SpannerSettings spannerSettings = spannerSettingsBuilder.build();
  * }</pre>
+ *
+ * Please refer to the [Client Side Retry
+ * Guide](https://github.com/googleapis/google-cloud-java/blob/main/docs/client_retries.md) for
+ * additional support in setting retries.
  */
 @Generated("by gapic-generator-java")
 public class SpannerSettings extends ClientSettings<SpannerSettings> {
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/stub/SpannerStubSettings.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/stub/SpannerStubSettings.java
index fa6b86633b3..ae4b1c11daf 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/stub/SpannerStubSettings.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/v1/stub/SpannerStubSettings.java
@@ -94,7 +94,9 @@
  * <p>The builder of this class is recursive, so contained classes are themselves builders. When
  * build() is called, the tree of builders is called to create the complete settings object.
  *
- * <p>For example, to set the total timeout of createSession to 30 seconds:
+ * <p>For example, to set the
+ * [RetrySettings](https://cloud.google.com/java/docs/reference/gax/latest/com.google.api.gax.retrying.RetrySettings)
+ * of createSession:
  *
  * <pre>{@code
  * // This snippet has been automatically generated and should be regarded as a code template only.
@@ -110,10 +112,21 @@
  *             .createSessionSettings()
  *             .getRetrySettings()
  *             .toBuilder()
- *             .setTotalTimeout(Duration.ofSeconds(30))
+ *             .setInitialRetryDelayDuration(Duration.ofSeconds(1))
+ *             .setInitialRpcTimeoutDuration(Duration.ofSeconds(5))
+ *             .setMaxAttempts(5)
+ *             .setMaxRetryDelayDuration(Duration.ofSeconds(30))
+ *             .setMaxRpcTimeoutDuration(Duration.ofSeconds(60))
+ *             .setRetryDelayMultiplier(1.3)
+ *             .setRpcTimeoutMultiplier(1.5)
+ *             .setTotalTimeoutDuration(Duration.ofSeconds(300))
  *             .build());
  * SpannerStubSettings spannerSettings = spannerSettingsBuilder.build();
  * }</pre>
+ *
+ * Please refer to the [Client Side Retry
+ * Guide](https://github.com/googleapis/google-cloud-java/blob/main/docs/client_retries.md) for
+ * additional support in setting retries.
  */
 @Generated("by gapic-generator-java")
 public class SpannerStubSettings extends StubSettings<SpannerStubSettings> {
@@ -177,9 +190,7 @@ public String extractNextToken(ListSessionsResponse payload) {
 
             @Override
             public Iterable<Session> extractResources(ListSessionsResponse payload) {
-              return payload.getSessionsList() == null
-                  ? ImmutableList.<Session>of()
-                  : payload.getSessionsList();
+              return payload.getSessionsList();
             }
           };
 
diff --git a/google-cloud-spanner/src/main/resources/META-INF/native-image/com.google.cloud.spanner.v1/reflect-config.json b/google-cloud-spanner/src/main/resources/META-INF/native-image/com.google.cloud.spanner.v1/reflect-config.json
index 4e56610da8f..ffa070f1225 100644
--- a/google-cloud-spanner/src/main/resources/META-INF/native-image/com.google.cloud.spanner.v1/reflect-config.json
+++ b/google-cloud-spanner/src/main/resources/META-INF/native-image/com.google.cloud.spanner.v1/reflect-config.json
@@ -305,6 +305,24 @@
     "allDeclaredClasses": true,
     "allPublicClasses": true
   },
+  {
+    "name": "com.google.api.PythonSettings$ExperimentalFeatures",
+    "queryAllDeclaredConstructors": true,
+    "queryAllPublicConstructors": true,
+    "queryAllDeclaredMethods": true,
+    "allPublicMethods": true,
+    "allDeclaredClasses": true,
+    "allPublicClasses": true
+  },
+  {
+    "name": "com.google.api.PythonSettings$ExperimentalFeatures$Builder",
+    "queryAllDeclaredConstructors": true,
+    "queryAllPublicConstructors": true,
+    "queryAllDeclaredMethods": true,
+    "allPublicMethods": true,
+    "allDeclaredClasses": true,
+    "allPublicClasses": true
+  },
   {
     "name": "com.google.api.ResourceDescriptor",
     "queryAllDeclaredConstructors": true,
@@ -1727,6 +1745,24 @@
     "allDeclaredClasses": true,
     "allPublicClasses": true
   },
+  {
+    "name": "com.google.spanner.v1.MultiplexedSessionPrecommitToken",
+    "queryAllDeclaredConstructors": true,
+    "queryAllPublicConstructors": true,
+    "queryAllDeclaredMethods": true,
+    "allPublicMethods": true,
+    "allDeclaredClasses": true,
+    "allPublicClasses": true
+  },
+  {
+    "name": "com.google.spanner.v1.MultiplexedSessionPrecommitToken$Builder",
+    "queryAllDeclaredConstructors": true,
+    "queryAllPublicConstructors": true,
+    "queryAllDeclaredMethods": true,
+    "allPublicMethods": true,
+    "allDeclaredClasses": true,
+    "allPublicClasses": true
+  },
   {
     "name": "com.google.spanner.v1.Mutation",
     "queryAllDeclaredConstructors": true,
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/CloseSpannerWithOpenResultSetTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/CloseSpannerWithOpenResultSetTest.java
index 67b14f60a4e..a489a269b22 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/CloseSpannerWithOpenResultSetTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/CloseSpannerWithOpenResultSetTest.java
@@ -39,6 +39,8 @@
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
@@ -59,6 +61,16 @@ Spanner createSpanner() {
         .getService();
   }
 
+  @BeforeClass
+  public static void setWatchdogTimeout() {
+    System.setProperty("com.google.cloud.spanner.watchdogTimeoutSeconds", "1");
+  }
+
+  @AfterClass
+  public static void clearWatchdogTimeout() {
+    System.clearProperty("com.google.cloud.spanner.watchdogTimeoutSeconds");
+  }
+
   @After
   public void cleanup() {
     mockSpanner.unfreeze();
@@ -75,7 +87,13 @@ public void testBatchClient_closedSpannerWithOpenResultSet_streamsAreCancelled()
             client.batchReadOnlyTransaction(TimestampBound.strong());
         ResultSet resultSet = transaction.executeQuery(SELECT_RANDOM_STATEMENT)) {
       mockSpanner.freezeAfterReturningNumRows(1);
-      assertTrue(resultSet.next());
+      // This can sometimes fail, as the mock server may not always actually return the first row.
+      try {
+        assertTrue(resultSet.next());
+      } catch (SpannerException exception) {
+        assertEquals(ErrorCode.DEADLINE_EXCEEDED, exception.getErrorCode());
+        return;
+      }
       ((SpannerImpl) spanner).close(1, TimeUnit.MILLISECONDS);
       // This should return an error as the stream is cancelled.
       SpannerException exception = assertThrows(SpannerException.class, resultSet::next);
@@ -93,7 +111,13 @@ public void testNormalDatabaseClient_closedSpannerWithOpenResultSet_sessionsAreD
     try (ReadOnlyTransaction transaction = client.readOnlyTransaction(TimestampBound.strong());
         ResultSet resultSet = transaction.executeQuery(SELECT_RANDOM_STATEMENT)) {
       mockSpanner.freezeAfterReturningNumRows(1);
-      assertTrue(resultSet.next());
+      // This can sometimes fail, as the mock server may not always actually return the first row.
+      try {
+        assertTrue(resultSet.next());
+      } catch (SpannerException exception) {
+        assertEquals(ErrorCode.DEADLINE_EXCEEDED, exception.getErrorCode());
+        return;
+      }
       List<ExecuteSqlRequest> executeSqlRequests =
           mockSpanner.getRequestsOfType(ExecuteSqlRequest.class).stream()
               .filter(request -> request.getSql().equals(SELECT_RANDOM_STATEMENT.getSql()))
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientHttpJsonTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientHttpJsonTest.java
index 3b5f106f13f..1683d533855 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientHttpJsonTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientHttpJsonTest.java
@@ -44,6 +44,7 @@
 import com.google.spanner.v1.ExecuteSqlRequest;
 import com.google.spanner.v1.KeySet;
 import com.google.spanner.v1.ListSessionsResponse;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.Mutation;
 import com.google.spanner.v1.Partition;
 import com.google.spanner.v1.PartitionOptions;
@@ -587,6 +588,7 @@ public void executeSqlTest() throws Exception {
             .setMetadata(ResultSetMetadata.newBuilder().build())
             .addAllRows(new ArrayList<ListValue>())
             .setStats(ResultSetStats.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockService.addResponse(expectedResponse);
 
@@ -673,6 +675,7 @@ public void executeBatchDmlTest() throws Exception {
         ExecuteBatchDmlResponse.newBuilder()
             .addAllResultSets(new ArrayList<ResultSet>())
             .setStatus(Status.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockService.addResponse(expectedResponse);
 
@@ -735,6 +738,7 @@ public void readTest() throws Exception {
             .setMetadata(ResultSetMetadata.newBuilder().build())
             .addAllRows(new ArrayList<ListValue>())
             .setStats(ResultSetStats.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockService.addResponse(expectedResponse);
 
@@ -821,6 +825,7 @@ public void beginTransactionTest() throws Exception {
         Transaction.newBuilder()
             .setId(ByteString.EMPTY)
             .setReadTimestamp(Timestamp.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockService.addResponse(expectedResponse);
 
@@ -868,6 +873,7 @@ public void beginTransactionTest2() throws Exception {
         Transaction.newBuilder()
             .setId(ByteString.EMPTY)
             .setReadTimestamp(Timestamp.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockService.addResponse(expectedResponse);
 
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientTest.java
index 22f578ac2bc..83caf7405d9 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/v1/SpannerClientTest.java
@@ -55,6 +55,7 @@
 import com.google.spanner.v1.KeySet;
 import com.google.spanner.v1.ListSessionsRequest;
 import com.google.spanner.v1.ListSessionsResponse;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.Mutation;
 import com.google.spanner.v1.PartialResultSet;
 import com.google.spanner.v1.Partition;
@@ -545,6 +546,7 @@ public void executeSqlTest() throws Exception {
             .setMetadata(ResultSetMetadata.newBuilder().build())
             .addAllRows(new ArrayList<ListValue>())
             .setStats(ResultSetStats.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockSpanner.addResponse(expectedResponse);
 
@@ -629,6 +631,7 @@ public void executeStreamingSqlTest() throws Exception {
             .setChunkedValue(true)
             .setResumeToken(ByteString.EMPTY)
             .setStats(ResultSetStats.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockSpanner.addResponse(expectedResponse);
     ExecuteSqlRequest request =
@@ -702,6 +705,7 @@ public void executeBatchDmlTest() throws Exception {
         ExecuteBatchDmlResponse.newBuilder()
             .addAllResultSets(new ArrayList<ResultSet>())
             .setStatus(Status.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockSpanner.addResponse(expectedResponse);
 
@@ -762,6 +766,7 @@ public void readTest() throws Exception {
             .setMetadata(ResultSetMetadata.newBuilder().build())
             .addAllRows(new ArrayList<ListValue>())
             .setStats(ResultSetStats.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockSpanner.addResponse(expectedResponse);
 
@@ -847,6 +852,7 @@ public void streamingReadTest() throws Exception {
             .setChunkedValue(true)
             .setResumeToken(ByteString.EMPTY)
             .setStats(ResultSetStats.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockSpanner.addResponse(expectedResponse);
     ReadRequest request =
@@ -920,6 +926,7 @@ public void beginTransactionTest() throws Exception {
         Transaction.newBuilder()
             .setId(ByteString.EMPTY)
             .setReadTimestamp(Timestamp.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockSpanner.addResponse(expectedResponse);
 
@@ -962,6 +969,7 @@ public void beginTransactionTest2() throws Exception {
         Transaction.newBuilder()
             .setId(ByteString.EMPTY)
             .setReadTimestamp(Timestamp.newBuilder().build())
+            .setPrecommitToken(MultiplexedSessionPrecommitToken.newBuilder().build())
             .build();
     mockSpanner.addResponse(expectedResponse);
 
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequest.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequest.java
index c2b54d6ce94..1a564ec3f5e 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequest.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequest.java
@@ -238,6 +238,68 @@ public com.google.spanner.v1.RequestOptionsOrBuilder getRequestOptionsOrBuilder(
         : requestOptions_;
   }
 
+  public static final int MUTATION_KEY_FIELD_NUMBER = 4;
+  private com.google.spanner.v1.Mutation mutationKey_;
+  /**
+   *
+   *
+   * <pre>
+   * Required for read-write transactions on a multiplexed session that commit
+   * mutations but do not perform any reads or queries.
+   * Clients should randomly select one of the mutations from the
+   * mutation set and send it as a part of this request.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the mutationKey field is set.
+   */
+  @java.lang.Override
+  public boolean hasMutationKey() {
+    return ((bitField0_ & 0x00000004) != 0);
+  }
+  /**
+   *
+   *
+   * <pre>
+   * Required for read-write transactions on a multiplexed session that commit
+   * mutations but do not perform any reads or queries.
+   * Clients should randomly select one of the mutations from the
+   * mutation set and send it as a part of this request.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The mutationKey.
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.Mutation getMutationKey() {
+    return mutationKey_ == null
+        ? com.google.spanner.v1.Mutation.getDefaultInstance()
+        : mutationKey_;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * Required for read-write transactions on a multiplexed session that commit
+   * mutations but do not perform any reads or queries.
+   * Clients should randomly select one of the mutations from the
+   * mutation set and send it as a part of this request.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MutationOrBuilder getMutationKeyOrBuilder() {
+    return mutationKey_ == null
+        ? com.google.spanner.v1.Mutation.getDefaultInstance()
+        : mutationKey_;
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -261,6 +323,9 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (((bitField0_ & 0x00000002) != 0)) {
       output.writeMessage(3, getRequestOptions());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      output.writeMessage(4, getMutationKey());
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -279,6 +344,9 @@ public int getSerializedSize() {
     if (((bitField0_ & 0x00000002) != 0)) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(3, getRequestOptions());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      size += com.google.protobuf.CodedOutputStream.computeMessageSize(4, getMutationKey());
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -304,6 +372,10 @@ public boolean equals(final java.lang.Object obj) {
     if (hasRequestOptions()) {
       if (!getRequestOptions().equals(other.getRequestOptions())) return false;
     }
+    if (hasMutationKey() != other.hasMutationKey()) return false;
+    if (hasMutationKey()) {
+      if (!getMutationKey().equals(other.getMutationKey())) return false;
+    }
     if (!getUnknownFields().equals(other.getUnknownFields())) return false;
     return true;
   }
@@ -325,6 +397,10 @@ public int hashCode() {
       hash = (37 * hash) + REQUEST_OPTIONS_FIELD_NUMBER;
       hash = (53 * hash) + getRequestOptions().hashCode();
     }
+    if (hasMutationKey()) {
+      hash = (37 * hash) + MUTATION_KEY_FIELD_NUMBER;
+      hash = (53 * hash) + getMutationKey().hashCode();
+    }
     hash = (29 * hash) + getUnknownFields().hashCode();
     memoizedHashCode = hash;
     return hash;
@@ -468,6 +544,7 @@ private void maybeForceBuilderInitialization() {
       if (com.google.protobuf.GeneratedMessageV3.alwaysUseFieldBuilders) {
         getOptionsFieldBuilder();
         getRequestOptionsFieldBuilder();
+        getMutationKeyFieldBuilder();
       }
     }
 
@@ -486,6 +563,11 @@ public Builder clear() {
         requestOptionsBuilder_.dispose();
         requestOptionsBuilder_ = null;
       }
+      mutationKey_ = null;
+      if (mutationKeyBuilder_ != null) {
+        mutationKeyBuilder_.dispose();
+        mutationKeyBuilder_ = null;
+      }
       return this;
     }
 
@@ -535,6 +617,11 @@ private void buildPartial0(com.google.spanner.v1.BeginTransactionRequest result)
             requestOptionsBuilder_ == null ? requestOptions_ : requestOptionsBuilder_.build();
         to_bitField0_ |= 0x00000002;
       }
+      if (((from_bitField0_ & 0x00000008) != 0)) {
+        result.mutationKey_ =
+            mutationKeyBuilder_ == null ? mutationKey_ : mutationKeyBuilder_.build();
+        to_bitField0_ |= 0x00000004;
+      }
       result.bitField0_ |= to_bitField0_;
     }
 
@@ -594,6 +681,9 @@ public Builder mergeFrom(com.google.spanner.v1.BeginTransactionRequest other) {
       if (other.hasRequestOptions()) {
         mergeRequestOptions(other.getRequestOptions());
       }
+      if (other.hasMutationKey()) {
+        mergeMutationKey(other.getMutationKey());
+      }
       this.mergeUnknownFields(other.getUnknownFields());
       onChanged();
       return this;
@@ -638,6 +728,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000004;
                 break;
               } // case 26
+            case 34:
+              {
+                input.readMessage(getMutationKeyFieldBuilder().getBuilder(), extensionRegistry);
+                bitField0_ |= 0x00000008;
+                break;
+              } // case 34
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -1197,6 +1293,227 @@ public com.google.spanner.v1.RequestOptionsOrBuilder getRequestOptionsOrBuilder(
       return requestOptionsBuilder_;
     }
 
+    private com.google.spanner.v1.Mutation mutationKey_;
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.Mutation,
+            com.google.spanner.v1.Mutation.Builder,
+            com.google.spanner.v1.MutationOrBuilder>
+        mutationKeyBuilder_;
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return Whether the mutationKey field is set.
+     */
+    public boolean hasMutationKey() {
+      return ((bitField0_ & 0x00000008) != 0);
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The mutationKey.
+     */
+    public com.google.spanner.v1.Mutation getMutationKey() {
+      if (mutationKeyBuilder_ == null) {
+        return mutationKey_ == null
+            ? com.google.spanner.v1.Mutation.getDefaultInstance()
+            : mutationKey_;
+      } else {
+        return mutationKeyBuilder_.getMessage();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setMutationKey(com.google.spanner.v1.Mutation value) {
+      if (mutationKeyBuilder_ == null) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        mutationKey_ = value;
+      } else {
+        mutationKeyBuilder_.setMessage(value);
+      }
+      bitField0_ |= 0x00000008;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setMutationKey(com.google.spanner.v1.Mutation.Builder builderForValue) {
+      if (mutationKeyBuilder_ == null) {
+        mutationKey_ = builderForValue.build();
+      } else {
+        mutationKeyBuilder_.setMessage(builderForValue.build());
+      }
+      bitField0_ |= 0x00000008;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder mergeMutationKey(com.google.spanner.v1.Mutation value) {
+      if (mutationKeyBuilder_ == null) {
+        if (((bitField0_ & 0x00000008) != 0)
+            && mutationKey_ != null
+            && mutationKey_ != com.google.spanner.v1.Mutation.getDefaultInstance()) {
+          getMutationKeyBuilder().mergeFrom(value);
+        } else {
+          mutationKey_ = value;
+        }
+      } else {
+        mutationKeyBuilder_.mergeFrom(value);
+      }
+      if (mutationKey_ != null) {
+        bitField0_ |= 0x00000008;
+        onChanged();
+      }
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder clearMutationKey() {
+      bitField0_ = (bitField0_ & ~0x00000008);
+      mutationKey_ = null;
+      if (mutationKeyBuilder_ != null) {
+        mutationKeyBuilder_.dispose();
+        mutationKeyBuilder_ = null;
+      }
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.Mutation.Builder getMutationKeyBuilder() {
+      bitField0_ |= 0x00000008;
+      onChanged();
+      return getMutationKeyFieldBuilder().getBuilder();
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MutationOrBuilder getMutationKeyOrBuilder() {
+      if (mutationKeyBuilder_ != null) {
+        return mutationKeyBuilder_.getMessageOrBuilder();
+      } else {
+        return mutationKey_ == null
+            ? com.google.spanner.v1.Mutation.getDefaultInstance()
+            : mutationKey_;
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Required for read-write transactions on a multiplexed session that commit
+     * mutations but do not perform any reads or queries.
+     * Clients should randomly select one of the mutations from the
+     * mutation set and send it as a part of this request.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.Mutation,
+            com.google.spanner.v1.Mutation.Builder,
+            com.google.spanner.v1.MutationOrBuilder>
+        getMutationKeyFieldBuilder() {
+      if (mutationKeyBuilder_ == null) {
+        mutationKeyBuilder_ =
+            new com.google.protobuf.SingleFieldBuilderV3<
+                com.google.spanner.v1.Mutation,
+                com.google.spanner.v1.Mutation.Builder,
+                com.google.spanner.v1.MutationOrBuilder>(
+                getMutationKey(), getParentForChildren(), isClean());
+        mutationKey_ = null;
+      }
+      return mutationKeyBuilder_;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequestOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequestOrBuilder.java
index f42a87a9df1..ceb5120da18 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequestOrBuilder.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/BeginTransactionRequestOrBuilder.java
@@ -140,4 +140,51 @@ public interface BeginTransactionRequestOrBuilder
    * <code>.google.spanner.v1.RequestOptions request_options = 3;</code>
    */
   com.google.spanner.v1.RequestOptionsOrBuilder getRequestOptionsOrBuilder();
+
+  /**
+   *
+   *
+   * <pre>
+   * Required for read-write transactions on a multiplexed session that commit
+   * mutations but do not perform any reads or queries.
+   * Clients should randomly select one of the mutations from the
+   * mutation set and send it as a part of this request.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the mutationKey field is set.
+   */
+  boolean hasMutationKey();
+  /**
+   *
+   *
+   * <pre>
+   * Required for read-write transactions on a multiplexed session that commit
+   * mutations but do not perform any reads or queries.
+   * Clients should randomly select one of the mutations from the
+   * mutation set and send it as a part of this request.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The mutationKey.
+   */
+  com.google.spanner.v1.Mutation getMutationKey();
+  /**
+   *
+   *
+   * <pre>
+   * Required for read-write transactions on a multiplexed session that commit
+   * mutations but do not perform any reads or queries.
+   * Clients should randomly select one of the mutations from the
+   * mutation set and send it as a part of this request.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.Mutation mutation_key = 4 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  com.google.spanner.v1.MutationOrBuilder getMutationKeyOrBuilder();
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequest.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequest.java
index cd3f62a2438..d17d62d3da4 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequest.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequest.java
@@ -495,6 +495,72 @@ public com.google.spanner.v1.RequestOptionsOrBuilder getRequestOptionsOrBuilder(
         : requestOptions_;
   }
 
+  public static final int PRECOMMIT_TOKEN_FIELD_NUMBER = 9;
+  private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+  /**
+   *
+   *
+   * <pre>
+   * If the read-write transaction was executed on a multiplexed session, the
+   * precommit token with the highest sequence number received
+   * in this transaction attempt, should be included here.
+   * Failing to do so will result in a FailedPrecondition error.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  @java.lang.Override
+  public boolean hasPrecommitToken() {
+    return ((bitField0_ & 0x00000004) != 0);
+  }
+  /**
+   *
+   *
+   * <pre>
+   * If the read-write transaction was executed on a multiplexed session, the
+   * precommit token with the highest sequence number received
+   * in this transaction attempt, should be included here.
+   * Failing to do so will result in a FailedPrecondition error.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * If the read-write transaction was executed on a multiplexed session, the
+   * precommit token with the highest sequence number received
+   * in this transaction attempt, should be included here.
+   * Failing to do so will result in a FailedPrecondition error.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+      getPrecommitTokenOrBuilder() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -530,6 +596,9 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (((bitField0_ & 0x00000001) != 0)) {
       output.writeMessage(8, getMaxCommitDelay());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      output.writeMessage(9, getPrecommitToken());
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -564,6 +633,9 @@ public int getSerializedSize() {
     if (((bitField0_ & 0x00000001) != 0)) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(8, getMaxCommitDelay());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      size += com.google.protobuf.CodedOutputStream.computeMessageSize(9, getPrecommitToken());
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -590,6 +662,10 @@ public boolean equals(final java.lang.Object obj) {
     if (hasRequestOptions()) {
       if (!getRequestOptions().equals(other.getRequestOptions())) return false;
     }
+    if (hasPrecommitToken() != other.hasPrecommitToken()) return false;
+    if (hasPrecommitToken()) {
+      if (!getPrecommitToken().equals(other.getPrecommitToken())) return false;
+    }
     if (!getTransactionCase().equals(other.getTransactionCase())) return false;
     switch (transactionCase_) {
       case 2:
@@ -628,6 +704,10 @@ public int hashCode() {
       hash = (37 * hash) + REQUEST_OPTIONS_FIELD_NUMBER;
       hash = (53 * hash) + getRequestOptions().hashCode();
     }
+    if (hasPrecommitToken()) {
+      hash = (37 * hash) + PRECOMMIT_TOKEN_FIELD_NUMBER;
+      hash = (53 * hash) + getPrecommitToken().hashCode();
+    }
     switch (transactionCase_) {
       case 2:
         hash = (37 * hash) + TRANSACTION_ID_FIELD_NUMBER;
@@ -782,6 +862,7 @@ private void maybeForceBuilderInitialization() {
         getMutationsFieldBuilder();
         getMaxCommitDelayFieldBuilder();
         getRequestOptionsFieldBuilder();
+        getPrecommitTokenFieldBuilder();
       }
     }
 
@@ -811,6 +892,11 @@ public Builder clear() {
         requestOptionsBuilder_.dispose();
         requestOptionsBuilder_ = null;
       }
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
       transactionCase_ = 0;
       transaction_ = null;
       return this;
@@ -879,6 +965,11 @@ private void buildPartial0(com.google.spanner.v1.CommitRequest result) {
             requestOptionsBuilder_ == null ? requestOptions_ : requestOptionsBuilder_.build();
         to_bitField0_ |= 0x00000002;
       }
+      if (((from_bitField0_ & 0x00000080) != 0)) {
+        result.precommitToken_ =
+            precommitTokenBuilder_ == null ? precommitToken_ : precommitTokenBuilder_.build();
+        to_bitField0_ |= 0x00000004;
+      }
       result.bitField0_ |= to_bitField0_;
     }
 
@@ -976,6 +1067,9 @@ public Builder mergeFrom(com.google.spanner.v1.CommitRequest other) {
       if (other.hasRequestOptions()) {
         mergeRequestOptions(other.getRequestOptions());
       }
+      if (other.hasPrecommitToken()) {
+        mergePrecommitToken(other.getPrecommitToken());
+      }
       switch (other.getTransactionCase()) {
         case TRANSACTION_ID:
           {
@@ -1067,6 +1161,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000020;
                 break;
               } // case 66
+            case 74:
+              {
+                input.readMessage(getPrecommitTokenFieldBuilder().getBuilder(), extensionRegistry);
+                bitField0_ |= 0x00000080;
+                break;
+              } // case 74
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -2434,6 +2534,241 @@ public com.google.spanner.v1.RequestOptionsOrBuilder getRequestOptionsOrBuilder(
       return requestOptionsBuilder_;
     }
 
+    private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        precommitTokenBuilder_;
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return Whether the precommitToken field is set.
+     */
+    public boolean hasPrecommitToken() {
+      return ((bitField0_ & 0x00000080) != 0);
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The precommitToken.
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+      if (precommitTokenBuilder_ == null) {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      } else {
+        return precommitTokenBuilder_.getMessage();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        precommitToken_ = value;
+      } else {
+        precommitTokenBuilder_.setMessage(value);
+      }
+      bitField0_ |= 0x00000080;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder builderForValue) {
+      if (precommitTokenBuilder_ == null) {
+        precommitToken_ = builderForValue.build();
+      } else {
+        precommitTokenBuilder_.setMessage(builderForValue.build());
+      }
+      bitField0_ |= 0x00000080;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder mergePrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (((bitField0_ & 0x00000080) != 0)
+            && precommitToken_ != null
+            && precommitToken_
+                != com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()) {
+          getPrecommitTokenBuilder().mergeFrom(value);
+        } else {
+          precommitToken_ = value;
+        }
+      } else {
+        precommitTokenBuilder_.mergeFrom(value);
+      }
+      if (precommitToken_ != null) {
+        bitField0_ |= 0x00000080;
+        onChanged();
+      }
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder clearPrecommitToken() {
+      bitField0_ = (bitField0_ & ~0x00000080);
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder
+        getPrecommitTokenBuilder() {
+      bitField0_ |= 0x00000080;
+      onChanged();
+      return getPrecommitTokenFieldBuilder().getBuilder();
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+        getPrecommitTokenOrBuilder() {
+      if (precommitTokenBuilder_ != null) {
+        return precommitTokenBuilder_.getMessageOrBuilder();
+      } else {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If the read-write transaction was executed on a multiplexed session, the
+     * precommit token with the highest sequence number received
+     * in this transaction attempt, should be included here.
+     * Failing to do so will result in a FailedPrecondition error.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        getPrecommitTokenFieldBuilder() {
+      if (precommitTokenBuilder_ == null) {
+        precommitTokenBuilder_ =
+            new com.google.protobuf.SingleFieldBuilderV3<
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+                com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>(
+                getPrecommitToken(), getParentForChildren(), isClean());
+        precommitToken_ = null;
+      }
+      return precommitTokenBuilder_;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequestOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequestOrBuilder.java
index ed19e5568e0..6974bb845d4 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequestOrBuilder.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitRequestOrBuilder.java
@@ -298,5 +298,55 @@ public interface CommitRequestOrBuilder
    */
   com.google.spanner.v1.RequestOptionsOrBuilder getRequestOptionsOrBuilder();
 
+  /**
+   *
+   *
+   * <pre>
+   * If the read-write transaction was executed on a multiplexed session, the
+   * precommit token with the highest sequence number received
+   * in this transaction attempt, should be included here.
+   * Failing to do so will result in a FailedPrecondition error.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  boolean hasPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * If the read-write transaction was executed on a multiplexed session, the
+   * precommit token with the highest sequence number received
+   * in this transaction attempt, should be included here.
+   * Failing to do so will result in a FailedPrecondition error.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * If the read-write transaction was executed on a multiplexed session, the
+   * precommit token with the highest sequence number received
+   * in this transaction attempt, should be included here.
+   * Failing to do so will result in a FailedPrecondition error.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 9 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder getPrecommitTokenOrBuilder();
+
   com.google.spanner.v1.CommitRequest.TransactionCase getTransactionCase();
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponse.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponse.java
index 05ae3b23bfc..f25539a148e 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponse.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponse.java
@@ -631,6 +631,52 @@ public com.google.spanner.v1.CommitResponse.CommitStats getDefaultInstanceForTyp
   }
 
   private int bitField0_;
+  private int multiplexedSessionRetryCase_ = 0;
+
+  @SuppressWarnings("serial")
+  private java.lang.Object multiplexedSessionRetry_;
+
+  public enum MultiplexedSessionRetryCase
+      implements
+          com.google.protobuf.Internal.EnumLite,
+          com.google.protobuf.AbstractMessage.InternalOneOfEnum {
+    PRECOMMIT_TOKEN(4),
+    MULTIPLEXEDSESSIONRETRY_NOT_SET(0);
+    private final int value;
+
+    private MultiplexedSessionRetryCase(int value) {
+      this.value = value;
+    }
+    /**
+     * @param value The number of the enum to look for.
+     * @return The enum associated with the given number.
+     * @deprecated Use {@link #forNumber(int)} instead.
+     */
+    @java.lang.Deprecated
+    public static MultiplexedSessionRetryCase valueOf(int value) {
+      return forNumber(value);
+    }
+
+    public static MultiplexedSessionRetryCase forNumber(int value) {
+      switch (value) {
+        case 4:
+          return PRECOMMIT_TOKEN;
+        case 0:
+          return MULTIPLEXEDSESSIONRETRY_NOT_SET;
+        default:
+          return null;
+      }
+    }
+
+    public int getNumber() {
+      return this.value;
+    }
+  };
+
+  public MultiplexedSessionRetryCase getMultiplexedSessionRetryCase() {
+    return MultiplexedSessionRetryCase.forNumber(multiplexedSessionRetryCase_);
+  }
+
   public static final int COMMIT_TIMESTAMP_FIELD_NUMBER = 1;
   private com.google.protobuf.Timestamp commitTimestamp_;
   /**
@@ -737,6 +783,61 @@ public com.google.spanner.v1.CommitResponse.CommitStatsOrBuilder getCommitStatsO
         : commitStats_;
   }
 
+  public static final int PRECOMMIT_TOKEN_FIELD_NUMBER = 4;
+  /**
+   *
+   *
+   * <pre>
+   * If specified, transaction has not committed yet.
+   * Clients must retry the commit with the new precommit token.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  @java.lang.Override
+  public boolean hasPrecommitToken() {
+    return multiplexedSessionRetryCase_ == 4;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * If specified, transaction has not committed yet.
+   * Clients must retry the commit with the new precommit token.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+   *
+   * @return The precommitToken.
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+    if (multiplexedSessionRetryCase_ == 4) {
+      return (com.google.spanner.v1.MultiplexedSessionPrecommitToken) multiplexedSessionRetry_;
+    }
+    return com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance();
+  }
+  /**
+   *
+   *
+   * <pre>
+   * If specified, transaction has not committed yet.
+   * Clients must retry the commit with the new precommit token.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+      getPrecommitTokenOrBuilder() {
+    if (multiplexedSessionRetryCase_ == 4) {
+      return (com.google.spanner.v1.MultiplexedSessionPrecommitToken) multiplexedSessionRetry_;
+    }
+    return com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance();
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -757,6 +858,10 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (((bitField0_ & 0x00000002) != 0)) {
       output.writeMessage(2, getCommitStats());
     }
+    if (multiplexedSessionRetryCase_ == 4) {
+      output.writeMessage(
+          4, (com.google.spanner.v1.MultiplexedSessionPrecommitToken) multiplexedSessionRetry_);
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -772,6 +877,11 @@ public int getSerializedSize() {
     if (((bitField0_ & 0x00000002) != 0)) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(2, getCommitStats());
     }
+    if (multiplexedSessionRetryCase_ == 4) {
+      size +=
+          com.google.protobuf.CodedOutputStream.computeMessageSize(
+              4, (com.google.spanner.v1.MultiplexedSessionPrecommitToken) multiplexedSessionRetry_);
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -795,6 +905,15 @@ public boolean equals(final java.lang.Object obj) {
     if (hasCommitStats()) {
       if (!getCommitStats().equals(other.getCommitStats())) return false;
     }
+    if (!getMultiplexedSessionRetryCase().equals(other.getMultiplexedSessionRetryCase()))
+      return false;
+    switch (multiplexedSessionRetryCase_) {
+      case 4:
+        if (!getPrecommitToken().equals(other.getPrecommitToken())) return false;
+        break;
+      case 0:
+      default:
+    }
     if (!getUnknownFields().equals(other.getUnknownFields())) return false;
     return true;
   }
@@ -814,6 +933,14 @@ public int hashCode() {
       hash = (37 * hash) + COMMIT_STATS_FIELD_NUMBER;
       hash = (53 * hash) + getCommitStats().hashCode();
     }
+    switch (multiplexedSessionRetryCase_) {
+      case 4:
+        hash = (37 * hash) + PRECOMMIT_TOKEN_FIELD_NUMBER;
+        hash = (53 * hash) + getPrecommitToken().hashCode();
+        break;
+      case 0:
+      default:
+    }
     hash = (29 * hash) + getUnknownFields().hashCode();
     memoizedHashCode = hash;
     return hash;
@@ -972,6 +1099,11 @@ public Builder clear() {
         commitStatsBuilder_.dispose();
         commitStatsBuilder_ = null;
       }
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.clear();
+      }
+      multiplexedSessionRetryCase_ = 0;
+      multiplexedSessionRetry_ = null;
       return this;
     }
 
@@ -1001,6 +1133,7 @@ public com.google.spanner.v1.CommitResponse buildPartial() {
       if (bitField0_ != 0) {
         buildPartial0(result);
       }
+      buildPartialOneofs(result);
       onBuilt();
       return result;
     }
@@ -1021,6 +1154,14 @@ private void buildPartial0(com.google.spanner.v1.CommitResponse result) {
       result.bitField0_ |= to_bitField0_;
     }
 
+    private void buildPartialOneofs(com.google.spanner.v1.CommitResponse result) {
+      result.multiplexedSessionRetryCase_ = multiplexedSessionRetryCase_;
+      result.multiplexedSessionRetry_ = this.multiplexedSessionRetry_;
+      if (multiplexedSessionRetryCase_ == 4 && precommitTokenBuilder_ != null) {
+        result.multiplexedSessionRetry_ = precommitTokenBuilder_.build();
+      }
+    }
+
     @java.lang.Override
     public Builder clone() {
       return super.clone();
@@ -1072,6 +1213,17 @@ public Builder mergeFrom(com.google.spanner.v1.CommitResponse other) {
       if (other.hasCommitStats()) {
         mergeCommitStats(other.getCommitStats());
       }
+      switch (other.getMultiplexedSessionRetryCase()) {
+        case PRECOMMIT_TOKEN:
+          {
+            mergePrecommitToken(other.getPrecommitToken());
+            break;
+          }
+        case MULTIPLEXEDSESSIONRETRY_NOT_SET:
+          {
+            break;
+          }
+      }
       this.mergeUnknownFields(other.getUnknownFields());
       onChanged();
       return this;
@@ -1110,6 +1262,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000002;
                 break;
               } // case 18
+            case 34:
+              {
+                input.readMessage(getPrecommitTokenFieldBuilder().getBuilder(), extensionRegistry);
+                multiplexedSessionRetryCase_ = 4;
+                break;
+              } // case 34
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -1127,6 +1285,20 @@ public Builder mergeFrom(
       return this;
     }
 
+    private int multiplexedSessionRetryCase_ = 0;
+    private java.lang.Object multiplexedSessionRetry_;
+
+    public MultiplexedSessionRetryCase getMultiplexedSessionRetryCase() {
+      return MultiplexedSessionRetryCase.forNumber(multiplexedSessionRetryCase_);
+    }
+
+    public Builder clearMultiplexedSessionRetry() {
+      multiplexedSessionRetryCase_ = 0;
+      multiplexedSessionRetry_ = null;
+      onChanged();
+      return this;
+    }
+
     private int bitField0_;
 
     private com.google.protobuf.Timestamp commitTimestamp_;
@@ -1519,6 +1691,230 @@ public com.google.spanner.v1.CommitResponse.CommitStatsOrBuilder getCommitStatsO
       return commitStatsBuilder_;
     }
 
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        precommitTokenBuilder_;
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     *
+     * @return Whether the precommitToken field is set.
+     */
+    @java.lang.Override
+    public boolean hasPrecommitToken() {
+      return multiplexedSessionRetryCase_ == 4;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     *
+     * @return The precommitToken.
+     */
+    @java.lang.Override
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+      if (precommitTokenBuilder_ == null) {
+        if (multiplexedSessionRetryCase_ == 4) {
+          return (com.google.spanner.v1.MultiplexedSessionPrecommitToken) multiplexedSessionRetry_;
+        }
+        return com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance();
+      } else {
+        if (multiplexedSessionRetryCase_ == 4) {
+          return precommitTokenBuilder_.getMessage();
+        }
+        return com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     */
+    public Builder setPrecommitToken(com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        multiplexedSessionRetry_ = value;
+        onChanged();
+      } else {
+        precommitTokenBuilder_.setMessage(value);
+      }
+      multiplexedSessionRetryCase_ = 4;
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     */
+    public Builder setPrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder builderForValue) {
+      if (precommitTokenBuilder_ == null) {
+        multiplexedSessionRetry_ = builderForValue.build();
+        onChanged();
+      } else {
+        precommitTokenBuilder_.setMessage(builderForValue.build());
+      }
+      multiplexedSessionRetryCase_ = 4;
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     */
+    public Builder mergePrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (multiplexedSessionRetryCase_ == 4
+            && multiplexedSessionRetry_
+                != com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()) {
+          multiplexedSessionRetry_ =
+              com.google.spanner.v1.MultiplexedSessionPrecommitToken.newBuilder(
+                      (com.google.spanner.v1.MultiplexedSessionPrecommitToken)
+                          multiplexedSessionRetry_)
+                  .mergeFrom(value)
+                  .buildPartial();
+        } else {
+          multiplexedSessionRetry_ = value;
+        }
+        onChanged();
+      } else {
+        if (multiplexedSessionRetryCase_ == 4) {
+          precommitTokenBuilder_.mergeFrom(value);
+        } else {
+          precommitTokenBuilder_.setMessage(value);
+        }
+      }
+      multiplexedSessionRetryCase_ = 4;
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     */
+    public Builder clearPrecommitToken() {
+      if (precommitTokenBuilder_ == null) {
+        if (multiplexedSessionRetryCase_ == 4) {
+          multiplexedSessionRetryCase_ = 0;
+          multiplexedSessionRetry_ = null;
+          onChanged();
+        }
+      } else {
+        if (multiplexedSessionRetryCase_ == 4) {
+          multiplexedSessionRetryCase_ = 0;
+          multiplexedSessionRetry_ = null;
+        }
+        precommitTokenBuilder_.clear();
+      }
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder
+        getPrecommitTokenBuilder() {
+      return getPrecommitTokenFieldBuilder().getBuilder();
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     */
+    @java.lang.Override
+    public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+        getPrecommitTokenOrBuilder() {
+      if ((multiplexedSessionRetryCase_ == 4) && (precommitTokenBuilder_ != null)) {
+        return precommitTokenBuilder_.getMessageOrBuilder();
+      } else {
+        if (multiplexedSessionRetryCase_ == 4) {
+          return (com.google.spanner.v1.MultiplexedSessionPrecommitToken) multiplexedSessionRetry_;
+        }
+        return com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * If specified, transaction has not committed yet.
+     * Clients must retry the commit with the new precommit token.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+     */
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        getPrecommitTokenFieldBuilder() {
+      if (precommitTokenBuilder_ == null) {
+        if (!(multiplexedSessionRetryCase_ == 4)) {
+          multiplexedSessionRetry_ =
+              com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance();
+        }
+        precommitTokenBuilder_ =
+            new com.google.protobuf.SingleFieldBuilderV3<
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+                com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>(
+                (com.google.spanner.v1.MultiplexedSessionPrecommitToken) multiplexedSessionRetry_,
+                getParentForChildren(),
+                isClean());
+        multiplexedSessionRetry_ = null;
+      }
+      multiplexedSessionRetryCase_ = 4;
+      onChanged();
+      return precommitTokenBuilder_;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseOrBuilder.java
index e21b58a3dfe..247605af06c 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseOrBuilder.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseOrBuilder.java
@@ -99,4 +99,44 @@ public interface CommitResponseOrBuilder
    * <code>.google.spanner.v1.CommitResponse.CommitStats commit_stats = 2;</code>
    */
   com.google.spanner.v1.CommitResponse.CommitStatsOrBuilder getCommitStatsOrBuilder();
+
+  /**
+   *
+   *
+   * <pre>
+   * If specified, transaction has not committed yet.
+   * Clients must retry the commit with the new precommit token.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  boolean hasPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * If specified, transaction has not committed yet.
+   * Clients must retry the commit with the new precommit token.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+   *
+   * @return The precommitToken.
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * If specified, transaction has not committed yet.
+   * Clients must retry the commit with the new precommit token.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 4;</code>
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder getPrecommitTokenOrBuilder();
+
+  com.google.spanner.v1.CommitResponse.MultiplexedSessionRetryCase getMultiplexedSessionRetryCase();
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseProto.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseProto.java
index 6a0c06b8018..292218c245b 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseProto.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/CommitResponseProto.java
@@ -47,22 +47,27 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
     java.lang.String[] descriptorData = {
       "\n\'google/spanner/v1/commit_response.prot"
           + "o\022\021google.spanner.v1\032\037google/protobuf/ti"
-          + "mestamp.proto\"\262\001\n\016CommitResponse\0224\n\020comm"
-          + "it_timestamp\030\001 \001(\0132\032.google.protobuf.Tim"
-          + "estamp\022C\n\014commit_stats\030\002 \001(\0132-.google.sp"
-          + "anner.v1.CommitResponse.CommitStats\032%\n\013C"
-          + "ommitStats\022\026\n\016mutation_count\030\001 \001(\003B\266\001\n\025c"
-          + "om.google.spanner.v1B\023CommitResponseProt"
-          + "oP\001Z5cloud.google.com/go/spanner/apiv1/s"
-          + "pannerpb;spannerpb\252\002\027Google.Cloud.Spanne"
-          + "r.V1\312\002\027Google\\Cloud\\Spanner\\V1\352\002\032Google:"
-          + ":Cloud::Spanner::V1b\006proto3"
+          + "mestamp.proto\032#google/spanner/v1/transac"
+          + "tion.proto\"\235\002\n\016CommitResponse\0224\n\020commit_"
+          + "timestamp\030\001 \001(\0132\032.google.protobuf.Timest"
+          + "amp\022C\n\014commit_stats\030\002 \001(\0132-.google.spann"
+          + "er.v1.CommitResponse.CommitStats\022N\n\017prec"
+          + "ommit_token\030\004 \001(\01323.google.spanner.v1.Mu"
+          + "ltiplexedSessionPrecommitTokenH\000\032%\n\013Comm"
+          + "itStats\022\026\n\016mutation_count\030\001 \001(\003B\031\n\027Multi"
+          + "plexedSessionRetryB\266\001\n\025com.google.spanne"
+          + "r.v1B\023CommitResponseProtoP\001Z5cloud.googl"
+          + "e.com/go/spanner/apiv1/spannerpb;spanner"
+          + "pb\252\002\027Google.Cloud.Spanner.V1\312\002\027Google\\Cl"
+          + "oud\\Spanner\\V1\352\002\032Google::Cloud::Spanner:"
+          + ":V1b\006proto3"
     };
     descriptor =
         com.google.protobuf.Descriptors.FileDescriptor.internalBuildGeneratedFileFrom(
             descriptorData,
             new com.google.protobuf.Descriptors.FileDescriptor[] {
               com.google.protobuf.TimestampProto.getDescriptor(),
+              com.google.spanner.v1.TransactionProto.getDescriptor(),
             });
     internal_static_google_spanner_v1_CommitResponse_descriptor =
         getDescriptor().getMessageTypes().get(0);
@@ -70,7 +75,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
         new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
             internal_static_google_spanner_v1_CommitResponse_descriptor,
             new java.lang.String[] {
-              "CommitTimestamp", "CommitStats",
+              "CommitTimestamp", "CommitStats", "PrecommitToken", "MultiplexedSessionRetry",
             });
     internal_static_google_spanner_v1_CommitResponse_CommitStats_descriptor =
         internal_static_google_spanner_v1_CommitResponse_descriptor.getNestedTypes().get(0);
@@ -81,6 +86,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
               "MutationCount",
             });
     com.google.protobuf.TimestampProto.getDescriptor();
+    com.google.spanner.v1.TransactionProto.getDescriptor();
   }
 
   // @@protoc_insertion_point(outer_class_scope)
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponse.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponse.java
index f60631a1097..9a818adecab 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponse.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponse.java
@@ -254,6 +254,75 @@ public com.google.rpc.StatusOrBuilder getStatusOrBuilder() {
     return status_ == null ? com.google.rpc.Status.getDefaultInstance() : status_;
   }
 
+  public static final int PRECOMMIT_TOKEN_FIELD_NUMBER = 3;
+  private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  @java.lang.Override
+  public boolean hasPrecommitToken() {
+    return ((bitField0_ & 0x00000002) != 0);
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+      getPrecommitTokenOrBuilder() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -274,6 +343,9 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (((bitField0_ & 0x00000001) != 0)) {
       output.writeMessage(2, getStatus());
     }
+    if (((bitField0_ & 0x00000002) != 0)) {
+      output.writeMessage(3, getPrecommitToken());
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -289,6 +361,9 @@ public int getSerializedSize() {
     if (((bitField0_ & 0x00000001) != 0)) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(2, getStatus());
     }
+    if (((bitField0_ & 0x00000002) != 0)) {
+      size += com.google.protobuf.CodedOutputStream.computeMessageSize(3, getPrecommitToken());
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -310,6 +385,10 @@ public boolean equals(final java.lang.Object obj) {
     if (hasStatus()) {
       if (!getStatus().equals(other.getStatus())) return false;
     }
+    if (hasPrecommitToken() != other.hasPrecommitToken()) return false;
+    if (hasPrecommitToken()) {
+      if (!getPrecommitToken().equals(other.getPrecommitToken())) return false;
+    }
     if (!getUnknownFields().equals(other.getUnknownFields())) return false;
     return true;
   }
@@ -329,6 +408,10 @@ public int hashCode() {
       hash = (37 * hash) + STATUS_FIELD_NUMBER;
       hash = (53 * hash) + getStatus().hashCode();
     }
+    if (hasPrecommitToken()) {
+      hash = (37 * hash) + PRECOMMIT_TOKEN_FIELD_NUMBER;
+      hash = (53 * hash) + getPrecommitToken().hashCode();
+    }
     hash = (29 * hash) + getUnknownFields().hashCode();
     memoizedHashCode = hash;
     return hash;
@@ -501,6 +584,7 @@ private void maybeForceBuilderInitialization() {
       if (com.google.protobuf.GeneratedMessageV3.alwaysUseFieldBuilders) {
         getResultSetsFieldBuilder();
         getStatusFieldBuilder();
+        getPrecommitTokenFieldBuilder();
       }
     }
 
@@ -520,6 +604,11 @@ public Builder clear() {
         statusBuilder_.dispose();
         statusBuilder_ = null;
       }
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
       return this;
     }
 
@@ -574,6 +663,11 @@ private void buildPartial0(com.google.spanner.v1.ExecuteBatchDmlResponse result)
         result.status_ = statusBuilder_ == null ? status_ : statusBuilder_.build();
         to_bitField0_ |= 0x00000001;
       }
+      if (((from_bitField0_ & 0x00000004) != 0)) {
+        result.precommitToken_ =
+            precommitTokenBuilder_ == null ? precommitToken_ : precommitTokenBuilder_.build();
+        to_bitField0_ |= 0x00000002;
+      }
       result.bitField0_ |= to_bitField0_;
     }
 
@@ -652,6 +746,9 @@ public Builder mergeFrom(com.google.spanner.v1.ExecuteBatchDmlResponse other) {
       if (other.hasStatus()) {
         mergeStatus(other.getStatus());
       }
+      if (other.hasPrecommitToken()) {
+        mergePrecommitToken(other.getPrecommitToken());
+      }
       this.mergeUnknownFields(other.getUnknownFields());
       onChanged();
       return this;
@@ -696,6 +793,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000002;
                 break;
               } // case 18
+            case 26:
+              {
+                input.readMessage(getPrecommitTokenFieldBuilder().getBuilder(), extensionRegistry);
+                bitField0_ |= 0x00000004;
+                break;
+              } // case 26
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -1392,6 +1495,250 @@ public com.google.rpc.StatusOrBuilder getStatusOrBuilder() {
       return statusBuilder_;
     }
 
+    private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        precommitTokenBuilder_;
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return Whether the precommitToken field is set.
+     */
+    public boolean hasPrecommitToken() {
+      return ((bitField0_ & 0x00000004) != 0);
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The precommitToken.
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+      if (precommitTokenBuilder_ == null) {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      } else {
+        return precommitTokenBuilder_.getMessage();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        precommitToken_ = value;
+      } else {
+        precommitTokenBuilder_.setMessage(value);
+      }
+      bitField0_ |= 0x00000004;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder builderForValue) {
+      if (precommitTokenBuilder_ == null) {
+        precommitToken_ = builderForValue.build();
+      } else {
+        precommitTokenBuilder_.setMessage(builderForValue.build());
+      }
+      bitField0_ |= 0x00000004;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder mergePrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (((bitField0_ & 0x00000004) != 0)
+            && precommitToken_ != null
+            && precommitToken_
+                != com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()) {
+          getPrecommitTokenBuilder().mergeFrom(value);
+        } else {
+          precommitToken_ = value;
+        }
+      } else {
+        precommitTokenBuilder_.mergeFrom(value);
+      }
+      if (precommitToken_ != null) {
+        bitField0_ |= 0x00000004;
+        onChanged();
+      }
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder clearPrecommitToken() {
+      bitField0_ = (bitField0_ & ~0x00000004);
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder
+        getPrecommitTokenBuilder() {
+      bitField0_ |= 0x00000004;
+      onChanged();
+      return getPrecommitTokenFieldBuilder().getBuilder();
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+        getPrecommitTokenOrBuilder() {
+      if (precommitTokenBuilder_ != null) {
+        return precommitTokenBuilder_.getMessageOrBuilder();
+      } else {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        getPrecommitTokenFieldBuilder() {
+      if (precommitTokenBuilder_ == null) {
+        precommitTokenBuilder_ =
+            new com.google.protobuf.SingleFieldBuilderV3<
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+                com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>(
+                getPrecommitToken(), getParentForChildren(), isClean());
+        precommitToken_ = null;
+      }
+      return precommitTokenBuilder_;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponseOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponseOrBuilder.java
index cac2a088624..551359460c3 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponseOrBuilder.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ExecuteBatchDmlResponseOrBuilder.java
@@ -152,4 +152,57 @@ public interface ExecuteBatchDmlResponseOrBuilder
    * <code>.google.rpc.Status status = 2;</code>
    */
   com.google.rpc.StatusOrBuilder getStatusOrBuilder();
+
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  boolean hasPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder getPrecommitTokenOrBuilder();
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitToken.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitToken.java
new file mode 100644
index 00000000000..e3538ba992b
--- /dev/null
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitToken.java
@@ -0,0 +1,648 @@
+/*
+ * Copyright 2023 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+// Generated by the protocol buffer compiler.  DO NOT EDIT!
+// source: google/spanner/v1/transaction.proto
+
+// Protobuf Java Version: 3.25.3
+package com.google.spanner.v1;
+
+/**
+ *
+ *
+ * <pre>
+ * When a read-write transaction is executed on a multiplexed session,
+ * this precommit token is sent back to the client
+ * as a part of the [Transaction] message in the BeginTransaction response and
+ * also as a part of the [ResultSet] and [PartialResultSet] responses.
+ * </pre>
+ *
+ * Protobuf type {@code google.spanner.v1.MultiplexedSessionPrecommitToken}
+ */
+public final class MultiplexedSessionPrecommitToken extends com.google.protobuf.GeneratedMessageV3
+    implements
+    // @@protoc_insertion_point(message_implements:google.spanner.v1.MultiplexedSessionPrecommitToken)
+    MultiplexedSessionPrecommitTokenOrBuilder {
+  private static final long serialVersionUID = 0L;
+  // Use MultiplexedSessionPrecommitToken.newBuilder() to construct.
+  private MultiplexedSessionPrecommitToken(
+      com.google.protobuf.GeneratedMessageV3.Builder<?> builder) {
+    super(builder);
+  }
+
+  private MultiplexedSessionPrecommitToken() {
+    precommitToken_ = com.google.protobuf.ByteString.EMPTY;
+  }
+
+  @java.lang.Override
+  @SuppressWarnings({"unused"})
+  protected java.lang.Object newInstance(UnusedPrivateParameter unused) {
+    return new MultiplexedSessionPrecommitToken();
+  }
+
+  public static final com.google.protobuf.Descriptors.Descriptor getDescriptor() {
+    return com.google.spanner.v1.TransactionProto
+        .internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_descriptor;
+  }
+
+  @java.lang.Override
+  protected com.google.protobuf.GeneratedMessageV3.FieldAccessorTable
+      internalGetFieldAccessorTable() {
+    return com.google.spanner.v1.TransactionProto
+        .internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_fieldAccessorTable
+        .ensureFieldAccessorsInitialized(
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.class,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder.class);
+  }
+
+  public static final int PRECOMMIT_TOKEN_FIELD_NUMBER = 1;
+  private com.google.protobuf.ByteString precommitToken_ = com.google.protobuf.ByteString.EMPTY;
+  /**
+   *
+   *
+   * <pre>
+   * Opaque precommit token.
+   * </pre>
+   *
+   * <code>bytes precommit_token = 1;</code>
+   *
+   * @return The precommitToken.
+   */
+  @java.lang.Override
+  public com.google.protobuf.ByteString getPrecommitToken() {
+    return precommitToken_;
+  }
+
+  public static final int SEQ_NUM_FIELD_NUMBER = 2;
+  private int seqNum_ = 0;
+  /**
+   *
+   *
+   * <pre>
+   * An incrementing seq number is generated on every precommit token
+   * that is returned. Clients should remember the precommit token with the
+   * highest sequence number from the current transaction attempt.
+   * </pre>
+   *
+   * <code>int32 seq_num = 2;</code>
+   *
+   * @return The seqNum.
+   */
+  @java.lang.Override
+  public int getSeqNum() {
+    return seqNum_;
+  }
+
+  private byte memoizedIsInitialized = -1;
+
+  @java.lang.Override
+  public final boolean isInitialized() {
+    byte isInitialized = memoizedIsInitialized;
+    if (isInitialized == 1) return true;
+    if (isInitialized == 0) return false;
+
+    memoizedIsInitialized = 1;
+    return true;
+  }
+
+  @java.lang.Override
+  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
+    if (!precommitToken_.isEmpty()) {
+      output.writeBytes(1, precommitToken_);
+    }
+    if (seqNum_ != 0) {
+      output.writeInt32(2, seqNum_);
+    }
+    getUnknownFields().writeTo(output);
+  }
+
+  @java.lang.Override
+  public int getSerializedSize() {
+    int size = memoizedSize;
+    if (size != -1) return size;
+
+    size = 0;
+    if (!precommitToken_.isEmpty()) {
+      size += com.google.protobuf.CodedOutputStream.computeBytesSize(1, precommitToken_);
+    }
+    if (seqNum_ != 0) {
+      size += com.google.protobuf.CodedOutputStream.computeInt32Size(2, seqNum_);
+    }
+    size += getUnknownFields().getSerializedSize();
+    memoizedSize = size;
+    return size;
+  }
+
+  @java.lang.Override
+  public boolean equals(final java.lang.Object obj) {
+    if (obj == this) {
+      return true;
+    }
+    if (!(obj instanceof com.google.spanner.v1.MultiplexedSessionPrecommitToken)) {
+      return super.equals(obj);
+    }
+    com.google.spanner.v1.MultiplexedSessionPrecommitToken other =
+        (com.google.spanner.v1.MultiplexedSessionPrecommitToken) obj;
+
+    if (!getPrecommitToken().equals(other.getPrecommitToken())) return false;
+    if (getSeqNum() != other.getSeqNum()) return false;
+    if (!getUnknownFields().equals(other.getUnknownFields())) return false;
+    return true;
+  }
+
+  @java.lang.Override
+  public int hashCode() {
+    if (memoizedHashCode != 0) {
+      return memoizedHashCode;
+    }
+    int hash = 41;
+    hash = (19 * hash) + getDescriptor().hashCode();
+    hash = (37 * hash) + PRECOMMIT_TOKEN_FIELD_NUMBER;
+    hash = (53 * hash) + getPrecommitToken().hashCode();
+    hash = (37 * hash) + SEQ_NUM_FIELD_NUMBER;
+    hash = (53 * hash) + getSeqNum();
+    hash = (29 * hash) + getUnknownFields().hashCode();
+    memoizedHashCode = hash;
+    return hash;
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      java.nio.ByteBuffer data) throws com.google.protobuf.InvalidProtocolBufferException {
+    return PARSER.parseFrom(data);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      java.nio.ByteBuffer data, com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+      throws com.google.protobuf.InvalidProtocolBufferException {
+    return PARSER.parseFrom(data, extensionRegistry);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      com.google.protobuf.ByteString data)
+      throws com.google.protobuf.InvalidProtocolBufferException {
+    return PARSER.parseFrom(data);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      com.google.protobuf.ByteString data,
+      com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+      throws com.google.protobuf.InvalidProtocolBufferException {
+    return PARSER.parseFrom(data, extensionRegistry);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(byte[] data)
+      throws com.google.protobuf.InvalidProtocolBufferException {
+    return PARSER.parseFrom(data);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      byte[] data, com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+      throws com.google.protobuf.InvalidProtocolBufferException {
+    return PARSER.parseFrom(data, extensionRegistry);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      java.io.InputStream input) throws java.io.IOException {
+    return com.google.protobuf.GeneratedMessageV3.parseWithIOException(PARSER, input);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      java.io.InputStream input, com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+      throws java.io.IOException {
+    return com.google.protobuf.GeneratedMessageV3.parseWithIOException(
+        PARSER, input, extensionRegistry);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseDelimitedFrom(
+      java.io.InputStream input) throws java.io.IOException {
+    return com.google.protobuf.GeneratedMessageV3.parseDelimitedWithIOException(PARSER, input);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseDelimitedFrom(
+      java.io.InputStream input, com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+      throws java.io.IOException {
+    return com.google.protobuf.GeneratedMessageV3.parseDelimitedWithIOException(
+        PARSER, input, extensionRegistry);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      com.google.protobuf.CodedInputStream input) throws java.io.IOException {
+    return com.google.protobuf.GeneratedMessageV3.parseWithIOException(PARSER, input);
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken parseFrom(
+      com.google.protobuf.CodedInputStream input,
+      com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+      throws java.io.IOException {
+    return com.google.protobuf.GeneratedMessageV3.parseWithIOException(
+        PARSER, input, extensionRegistry);
+  }
+
+  @java.lang.Override
+  public Builder newBuilderForType() {
+    return newBuilder();
+  }
+
+  public static Builder newBuilder() {
+    return DEFAULT_INSTANCE.toBuilder();
+  }
+
+  public static Builder newBuilder(
+      com.google.spanner.v1.MultiplexedSessionPrecommitToken prototype) {
+    return DEFAULT_INSTANCE.toBuilder().mergeFrom(prototype);
+  }
+
+  @java.lang.Override
+  public Builder toBuilder() {
+    return this == DEFAULT_INSTANCE ? new Builder() : new Builder().mergeFrom(this);
+  }
+
+  @java.lang.Override
+  protected Builder newBuilderForType(com.google.protobuf.GeneratedMessageV3.BuilderParent parent) {
+    Builder builder = new Builder(parent);
+    return builder;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * When a read-write transaction is executed on a multiplexed session,
+   * this precommit token is sent back to the client
+   * as a part of the [Transaction] message in the BeginTransaction response and
+   * also as a part of the [ResultSet] and [PartialResultSet] responses.
+   * </pre>
+   *
+   * Protobuf type {@code google.spanner.v1.MultiplexedSessionPrecommitToken}
+   */
+  public static final class Builder extends com.google.protobuf.GeneratedMessageV3.Builder<Builder>
+      implements
+      // @@protoc_insertion_point(builder_implements:google.spanner.v1.MultiplexedSessionPrecommitToken)
+      com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder {
+    public static final com.google.protobuf.Descriptors.Descriptor getDescriptor() {
+      return com.google.spanner.v1.TransactionProto
+          .internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_descriptor;
+    }
+
+    @java.lang.Override
+    protected com.google.protobuf.GeneratedMessageV3.FieldAccessorTable
+        internalGetFieldAccessorTable() {
+      return com.google.spanner.v1.TransactionProto
+          .internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_fieldAccessorTable
+          .ensureFieldAccessorsInitialized(
+              com.google.spanner.v1.MultiplexedSessionPrecommitToken.class,
+              com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder.class);
+    }
+
+    // Construct using com.google.spanner.v1.MultiplexedSessionPrecommitToken.newBuilder()
+    private Builder() {}
+
+    private Builder(com.google.protobuf.GeneratedMessageV3.BuilderParent parent) {
+      super(parent);
+    }
+
+    @java.lang.Override
+    public Builder clear() {
+      super.clear();
+      bitField0_ = 0;
+      precommitToken_ = com.google.protobuf.ByteString.EMPTY;
+      seqNum_ = 0;
+      return this;
+    }
+
+    @java.lang.Override
+    public com.google.protobuf.Descriptors.Descriptor getDescriptorForType() {
+      return com.google.spanner.v1.TransactionProto
+          .internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_descriptor;
+    }
+
+    @java.lang.Override
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken getDefaultInstanceForType() {
+      return com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance();
+    }
+
+    @java.lang.Override
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken build() {
+      com.google.spanner.v1.MultiplexedSessionPrecommitToken result = buildPartial();
+      if (!result.isInitialized()) {
+        throw newUninitializedMessageException(result);
+      }
+      return result;
+    }
+
+    @java.lang.Override
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken buildPartial() {
+      com.google.spanner.v1.MultiplexedSessionPrecommitToken result =
+          new com.google.spanner.v1.MultiplexedSessionPrecommitToken(this);
+      if (bitField0_ != 0) {
+        buildPartial0(result);
+      }
+      onBuilt();
+      return result;
+    }
+
+    private void buildPartial0(com.google.spanner.v1.MultiplexedSessionPrecommitToken result) {
+      int from_bitField0_ = bitField0_;
+      if (((from_bitField0_ & 0x00000001) != 0)) {
+        result.precommitToken_ = precommitToken_;
+      }
+      if (((from_bitField0_ & 0x00000002) != 0)) {
+        result.seqNum_ = seqNum_;
+      }
+    }
+
+    @java.lang.Override
+    public Builder clone() {
+      return super.clone();
+    }
+
+    @java.lang.Override
+    public Builder setField(
+        com.google.protobuf.Descriptors.FieldDescriptor field, java.lang.Object value) {
+      return super.setField(field, value);
+    }
+
+    @java.lang.Override
+    public Builder clearField(com.google.protobuf.Descriptors.FieldDescriptor field) {
+      return super.clearField(field);
+    }
+
+    @java.lang.Override
+    public Builder clearOneof(com.google.protobuf.Descriptors.OneofDescriptor oneof) {
+      return super.clearOneof(oneof);
+    }
+
+    @java.lang.Override
+    public Builder setRepeatedField(
+        com.google.protobuf.Descriptors.FieldDescriptor field, int index, java.lang.Object value) {
+      return super.setRepeatedField(field, index, value);
+    }
+
+    @java.lang.Override
+    public Builder addRepeatedField(
+        com.google.protobuf.Descriptors.FieldDescriptor field, java.lang.Object value) {
+      return super.addRepeatedField(field, value);
+    }
+
+    @java.lang.Override
+    public Builder mergeFrom(com.google.protobuf.Message other) {
+      if (other instanceof com.google.spanner.v1.MultiplexedSessionPrecommitToken) {
+        return mergeFrom((com.google.spanner.v1.MultiplexedSessionPrecommitToken) other);
+      } else {
+        super.mergeFrom(other);
+        return this;
+      }
+    }
+
+    public Builder mergeFrom(com.google.spanner.v1.MultiplexedSessionPrecommitToken other) {
+      if (other == com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance())
+        return this;
+      if (other.getPrecommitToken() != com.google.protobuf.ByteString.EMPTY) {
+        setPrecommitToken(other.getPrecommitToken());
+      }
+      if (other.getSeqNum() != 0) {
+        setSeqNum(other.getSeqNum());
+      }
+      this.mergeUnknownFields(other.getUnknownFields());
+      onChanged();
+      return this;
+    }
+
+    @java.lang.Override
+    public final boolean isInitialized() {
+      return true;
+    }
+
+    @java.lang.Override
+    public Builder mergeFrom(
+        com.google.protobuf.CodedInputStream input,
+        com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+        throws java.io.IOException {
+      if (extensionRegistry == null) {
+        throw new java.lang.NullPointerException();
+      }
+      try {
+        boolean done = false;
+        while (!done) {
+          int tag = input.readTag();
+          switch (tag) {
+            case 0:
+              done = true;
+              break;
+            case 10:
+              {
+                precommitToken_ = input.readBytes();
+                bitField0_ |= 0x00000001;
+                break;
+              } // case 10
+            case 16:
+              {
+                seqNum_ = input.readInt32();
+                bitField0_ |= 0x00000002;
+                break;
+              } // case 16
+            default:
+              {
+                if (!super.parseUnknownField(input, extensionRegistry, tag)) {
+                  done = true; // was an endgroup tag
+                }
+                break;
+              } // default:
+          } // switch (tag)
+        } // while (!done)
+      } catch (com.google.protobuf.InvalidProtocolBufferException e) {
+        throw e.unwrapIOException();
+      } finally {
+        onChanged();
+      } // finally
+      return this;
+    }
+
+    private int bitField0_;
+
+    private com.google.protobuf.ByteString precommitToken_ = com.google.protobuf.ByteString.EMPTY;
+    /**
+     *
+     *
+     * <pre>
+     * Opaque precommit token.
+     * </pre>
+     *
+     * <code>bytes precommit_token = 1;</code>
+     *
+     * @return The precommitToken.
+     */
+    @java.lang.Override
+    public com.google.protobuf.ByteString getPrecommitToken() {
+      return precommitToken_;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Opaque precommit token.
+     * </pre>
+     *
+     * <code>bytes precommit_token = 1;</code>
+     *
+     * @param value The precommitToken to set.
+     * @return This builder for chaining.
+     */
+    public Builder setPrecommitToken(com.google.protobuf.ByteString value) {
+      if (value == null) {
+        throw new NullPointerException();
+      }
+      precommitToken_ = value;
+      bitField0_ |= 0x00000001;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * Opaque precommit token.
+     * </pre>
+     *
+     * <code>bytes precommit_token = 1;</code>
+     *
+     * @return This builder for chaining.
+     */
+    public Builder clearPrecommitToken() {
+      bitField0_ = (bitField0_ & ~0x00000001);
+      precommitToken_ = getDefaultInstance().getPrecommitToken();
+      onChanged();
+      return this;
+    }
+
+    private int seqNum_;
+    /**
+     *
+     *
+     * <pre>
+     * An incrementing seq number is generated on every precommit token
+     * that is returned. Clients should remember the precommit token with the
+     * highest sequence number from the current transaction attempt.
+     * </pre>
+     *
+     * <code>int32 seq_num = 2;</code>
+     *
+     * @return The seqNum.
+     */
+    @java.lang.Override
+    public int getSeqNum() {
+      return seqNum_;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * An incrementing seq number is generated on every precommit token
+     * that is returned. Clients should remember the precommit token with the
+     * highest sequence number from the current transaction attempt.
+     * </pre>
+     *
+     * <code>int32 seq_num = 2;</code>
+     *
+     * @param value The seqNum to set.
+     * @return This builder for chaining.
+     */
+    public Builder setSeqNum(int value) {
+
+      seqNum_ = value;
+      bitField0_ |= 0x00000002;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * An incrementing seq number is generated on every precommit token
+     * that is returned. Clients should remember the precommit token with the
+     * highest sequence number from the current transaction attempt.
+     * </pre>
+     *
+     * <code>int32 seq_num = 2;</code>
+     *
+     * @return This builder for chaining.
+     */
+    public Builder clearSeqNum() {
+      bitField0_ = (bitField0_ & ~0x00000002);
+      seqNum_ = 0;
+      onChanged();
+      return this;
+    }
+
+    @java.lang.Override
+    public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
+      return super.setUnknownFields(unknownFields);
+    }
+
+    @java.lang.Override
+    public final Builder mergeUnknownFields(
+        final com.google.protobuf.UnknownFieldSet unknownFields) {
+      return super.mergeUnknownFields(unknownFields);
+    }
+
+    // @@protoc_insertion_point(builder_scope:google.spanner.v1.MultiplexedSessionPrecommitToken)
+  }
+
+  // @@protoc_insertion_point(class_scope:google.spanner.v1.MultiplexedSessionPrecommitToken)
+  private static final com.google.spanner.v1.MultiplexedSessionPrecommitToken DEFAULT_INSTANCE;
+
+  static {
+    DEFAULT_INSTANCE = new com.google.spanner.v1.MultiplexedSessionPrecommitToken();
+  }
+
+  public static com.google.spanner.v1.MultiplexedSessionPrecommitToken getDefaultInstance() {
+    return DEFAULT_INSTANCE;
+  }
+
+  private static final com.google.protobuf.Parser<MultiplexedSessionPrecommitToken> PARSER =
+      new com.google.protobuf.AbstractParser<MultiplexedSessionPrecommitToken>() {
+        @java.lang.Override
+        public MultiplexedSessionPrecommitToken parsePartialFrom(
+            com.google.protobuf.CodedInputStream input,
+            com.google.protobuf.ExtensionRegistryLite extensionRegistry)
+            throws com.google.protobuf.InvalidProtocolBufferException {
+          Builder builder = newBuilder();
+          try {
+            builder.mergeFrom(input, extensionRegistry);
+          } catch (com.google.protobuf.InvalidProtocolBufferException e) {
+            throw e.setUnfinishedMessage(builder.buildPartial());
+          } catch (com.google.protobuf.UninitializedMessageException e) {
+            throw e.asInvalidProtocolBufferException().setUnfinishedMessage(builder.buildPartial());
+          } catch (java.io.IOException e) {
+            throw new com.google.protobuf.InvalidProtocolBufferException(e)
+                .setUnfinishedMessage(builder.buildPartial());
+          }
+          return builder.buildPartial();
+        }
+      };
+
+  public static com.google.protobuf.Parser<MultiplexedSessionPrecommitToken> parser() {
+    return PARSER;
+  }
+
+  @java.lang.Override
+  public com.google.protobuf.Parser<MultiplexedSessionPrecommitToken> getParserForType() {
+    return PARSER;
+  }
+
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitToken getDefaultInstanceForType() {
+    return DEFAULT_INSTANCE;
+  }
+}
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitTokenOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitTokenOrBuilder.java
new file mode 100644
index 00000000000..31caeab1b31
--- /dev/null
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/MultiplexedSessionPrecommitTokenOrBuilder.java
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2023 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+// Generated by the protocol buffer compiler.  DO NOT EDIT!
+// source: google/spanner/v1/transaction.proto
+
+// Protobuf Java Version: 3.25.3
+package com.google.spanner.v1;
+
+public interface MultiplexedSessionPrecommitTokenOrBuilder
+    extends
+    // @@protoc_insertion_point(interface_extends:google.spanner.v1.MultiplexedSessionPrecommitToken)
+    com.google.protobuf.MessageOrBuilder {
+
+  /**
+   *
+   *
+   * <pre>
+   * Opaque precommit token.
+   * </pre>
+   *
+   * <code>bytes precommit_token = 1;</code>
+   *
+   * @return The precommitToken.
+   */
+  com.google.protobuf.ByteString getPrecommitToken();
+
+  /**
+   *
+   *
+   * <pre>
+   * An incrementing seq number is generated on every precommit token
+   * that is returned. Clients should remember the precommit token with the
+   * highest sequence number from the current transaction attempt.
+   * </pre>
+   *
+   * <code>int32 seq_num = 2;</code>
+   *
+   * @return The seqNum.
+   */
+  int getSeqNum();
+}
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSet.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSet.java
index 9cd2a3dca19..403a61b5231 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSet.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSet.java
@@ -653,6 +653,75 @@ public com.google.spanner.v1.ResultSetStatsOrBuilder getStatsOrBuilder() {
     return stats_ == null ? com.google.spanner.v1.ResultSetStats.getDefaultInstance() : stats_;
   }
 
+  public static final int PRECOMMIT_TOKEN_FIELD_NUMBER = 8;
+  private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  @java.lang.Override
+  public boolean hasPrecommitToken() {
+    return ((bitField0_ & 0x00000004) != 0);
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+      getPrecommitTokenOrBuilder() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -682,6 +751,9 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (((bitField0_ & 0x00000002) != 0)) {
       output.writeMessage(5, getStats());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      output.writeMessage(8, getPrecommitToken());
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -706,6 +778,9 @@ public int getSerializedSize() {
     if (((bitField0_ & 0x00000002) != 0)) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(5, getStats());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      size += com.google.protobuf.CodedOutputStream.computeMessageSize(8, getPrecommitToken());
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -732,6 +807,10 @@ public boolean equals(final java.lang.Object obj) {
     if (hasStats()) {
       if (!getStats().equals(other.getStats())) return false;
     }
+    if (hasPrecommitToken() != other.hasPrecommitToken()) return false;
+    if (hasPrecommitToken()) {
+      if (!getPrecommitToken().equals(other.getPrecommitToken())) return false;
+    }
     if (!getUnknownFields().equals(other.getUnknownFields())) return false;
     return true;
   }
@@ -759,6 +838,10 @@ public int hashCode() {
       hash = (37 * hash) + STATS_FIELD_NUMBER;
       hash = (53 * hash) + getStats().hashCode();
     }
+    if (hasPrecommitToken()) {
+      hash = (37 * hash) + PRECOMMIT_TOKEN_FIELD_NUMBER;
+      hash = (53 * hash) + getPrecommitToken().hashCode();
+    }
     hash = (29 * hash) + getUnknownFields().hashCode();
     memoizedHashCode = hash;
     return hash;
@@ -904,6 +987,7 @@ private void maybeForceBuilderInitialization() {
         getMetadataFieldBuilder();
         getValuesFieldBuilder();
         getStatsFieldBuilder();
+        getPrecommitTokenFieldBuilder();
       }
     }
 
@@ -930,6 +1014,11 @@ public Builder clear() {
         statsBuilder_.dispose();
         statsBuilder_ = null;
       }
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
       return this;
     }
 
@@ -994,6 +1083,11 @@ private void buildPartial0(com.google.spanner.v1.PartialResultSet result) {
         result.stats_ = statsBuilder_ == null ? stats_ : statsBuilder_.build();
         to_bitField0_ |= 0x00000002;
       }
+      if (((from_bitField0_ & 0x00000020) != 0)) {
+        result.precommitToken_ =
+            precommitTokenBuilder_ == null ? precommitToken_ : precommitTokenBuilder_.build();
+        to_bitField0_ |= 0x00000004;
+      }
       result.bitField0_ |= to_bitField0_;
     }
 
@@ -1081,6 +1175,9 @@ public Builder mergeFrom(com.google.spanner.v1.PartialResultSet other) {
       if (other.hasStats()) {
         mergeStats(other.getStats());
       }
+      if (other.hasPrecommitToken()) {
+        mergePrecommitToken(other.getPrecommitToken());
+      }
       this.mergeUnknownFields(other.getUnknownFields());
       onChanged();
       return this;
@@ -1143,6 +1240,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000010;
                 break;
               } // case 42
+            case 66:
+              {
+                input.readMessage(getPrecommitTokenFieldBuilder().getBuilder(), extensionRegistry);
+                bitField0_ |= 0x00000020;
+                break;
+              } // case 66
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -3346,6 +3449,250 @@ public com.google.spanner.v1.ResultSetStatsOrBuilder getStatsOrBuilder() {
       return statsBuilder_;
     }
 
+    private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        precommitTokenBuilder_;
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return Whether the precommitToken field is set.
+     */
+    public boolean hasPrecommitToken() {
+      return ((bitField0_ & 0x00000020) != 0);
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The precommitToken.
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+      if (precommitTokenBuilder_ == null) {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      } else {
+        return precommitTokenBuilder_.getMessage();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        precommitToken_ = value;
+      } else {
+        precommitTokenBuilder_.setMessage(value);
+      }
+      bitField0_ |= 0x00000020;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder builderForValue) {
+      if (precommitTokenBuilder_ == null) {
+        precommitToken_ = builderForValue.build();
+      } else {
+        precommitTokenBuilder_.setMessage(builderForValue.build());
+      }
+      bitField0_ |= 0x00000020;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder mergePrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (((bitField0_ & 0x00000020) != 0)
+            && precommitToken_ != null
+            && precommitToken_
+                != com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()) {
+          getPrecommitTokenBuilder().mergeFrom(value);
+        } else {
+          precommitToken_ = value;
+        }
+      } else {
+        precommitTokenBuilder_.mergeFrom(value);
+      }
+      if (precommitToken_ != null) {
+        bitField0_ |= 0x00000020;
+        onChanged();
+      }
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder clearPrecommitToken() {
+      bitField0_ = (bitField0_ & ~0x00000020);
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder
+        getPrecommitTokenBuilder() {
+      bitField0_ |= 0x00000020;
+      onChanged();
+      return getPrecommitTokenFieldBuilder().getBuilder();
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+        getPrecommitTokenOrBuilder() {
+      if (precommitTokenBuilder_ != null) {
+        return precommitTokenBuilder_.getMessageOrBuilder();
+      } else {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        getPrecommitTokenFieldBuilder() {
+      if (precommitTokenBuilder_ == null) {
+        precommitTokenBuilder_ =
+            new com.google.protobuf.SingleFieldBuilderV3<
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+                com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>(
+                getPrecommitToken(), getParentForChildren(), isClean());
+        precommitToken_ = null;
+      }
+      return precommitTokenBuilder_;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSetOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSetOrBuilder.java
index 2e743fd893e..d5f8aecc044 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSetOrBuilder.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/PartialResultSetOrBuilder.java
@@ -554,4 +554,57 @@ public interface PartialResultSetOrBuilder
    * <code>.google.spanner.v1.ResultSetStats stats = 5;</code>
    */
   com.google.spanner.v1.ResultSetStatsOrBuilder getStatsOrBuilder();
+
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  boolean hasPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 8 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder getPrecommitTokenOrBuilder();
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSet.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSet.java
index 6140bf77e6e..9def6101bbc 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSet.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSet.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/result_set.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 /**
@@ -276,6 +276,75 @@ public com.google.spanner.v1.ResultSetStatsOrBuilder getStatsOrBuilder() {
     return stats_ == null ? com.google.spanner.v1.ResultSetStats.getDefaultInstance() : stats_;
   }
 
+  public static final int PRECOMMIT_TOKEN_FIELD_NUMBER = 5;
+  private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  @java.lang.Override
+  public boolean hasPrecommitToken() {
+    return ((bitField0_ & 0x00000004) != 0);
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+      getPrecommitTokenOrBuilder() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -299,6 +368,9 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (((bitField0_ & 0x00000002) != 0)) {
       output.writeMessage(3, getStats());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      output.writeMessage(5, getPrecommitToken());
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -317,6 +389,9 @@ public int getSerializedSize() {
     if (((bitField0_ & 0x00000002) != 0)) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(3, getStats());
     }
+    if (((bitField0_ & 0x00000004) != 0)) {
+      size += com.google.protobuf.CodedOutputStream.computeMessageSize(5, getPrecommitToken());
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -341,6 +416,10 @@ public boolean equals(final java.lang.Object obj) {
     if (hasStats()) {
       if (!getStats().equals(other.getStats())) return false;
     }
+    if (hasPrecommitToken() != other.hasPrecommitToken()) return false;
+    if (hasPrecommitToken()) {
+      if (!getPrecommitToken().equals(other.getPrecommitToken())) return false;
+    }
     if (!getUnknownFields().equals(other.getUnknownFields())) return false;
     return true;
   }
@@ -364,6 +443,10 @@ public int hashCode() {
       hash = (37 * hash) + STATS_FIELD_NUMBER;
       hash = (53 * hash) + getStats().hashCode();
     }
+    if (hasPrecommitToken()) {
+      hash = (37 * hash) + PRECOMMIT_TOKEN_FIELD_NUMBER;
+      hash = (53 * hash) + getPrecommitToken().hashCode();
+    }
     hash = (29 * hash) + getUnknownFields().hashCode();
     memoizedHashCode = hash;
     return hash;
@@ -506,6 +589,7 @@ private void maybeForceBuilderInitialization() {
         getMetadataFieldBuilder();
         getRowsFieldBuilder();
         getStatsFieldBuilder();
+        getPrecommitTokenFieldBuilder();
       }
     }
 
@@ -530,6 +614,11 @@ public Builder clear() {
         statsBuilder_.dispose();
         statsBuilder_ = null;
       }
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
       return this;
     }
 
@@ -587,6 +676,11 @@ private void buildPartial0(com.google.spanner.v1.ResultSet result) {
         result.stats_ = statsBuilder_ == null ? stats_ : statsBuilder_.build();
         to_bitField0_ |= 0x00000002;
       }
+      if (((from_bitField0_ & 0x00000008) != 0)) {
+        result.precommitToken_ =
+            precommitTokenBuilder_ == null ? precommitToken_ : precommitTokenBuilder_.build();
+        to_bitField0_ |= 0x00000004;
+      }
       result.bitField0_ |= to_bitField0_;
     }
 
@@ -668,6 +762,9 @@ public Builder mergeFrom(com.google.spanner.v1.ResultSet other) {
       if (other.hasStats()) {
         mergeStats(other.getStats());
       }
+      if (other.hasPrecommitToken()) {
+        mergePrecommitToken(other.getPrecommitToken());
+      }
       this.mergeUnknownFields(other.getUnknownFields());
       onChanged();
       return this;
@@ -718,6 +815,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000004;
                 break;
               } // case 26
+            case 42:
+              {
+                input.readMessage(getPrecommitTokenFieldBuilder().getBuilder(), extensionRegistry);
+                bitField0_ |= 0x00000008;
+                break;
+              } // case 42
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -1598,6 +1701,250 @@ public com.google.spanner.v1.ResultSetStatsOrBuilder getStatsOrBuilder() {
       return statsBuilder_;
     }
 
+    private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        precommitTokenBuilder_;
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return Whether the precommitToken field is set.
+     */
+    public boolean hasPrecommitToken() {
+      return ((bitField0_ & 0x00000008) != 0);
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The precommitToken.
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+      if (precommitTokenBuilder_ == null) {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      } else {
+        return precommitTokenBuilder_.getMessage();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        precommitToken_ = value;
+      } else {
+        precommitTokenBuilder_.setMessage(value);
+      }
+      bitField0_ |= 0x00000008;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder setPrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder builderForValue) {
+      if (precommitTokenBuilder_ == null) {
+        precommitToken_ = builderForValue.build();
+      } else {
+        precommitTokenBuilder_.setMessage(builderForValue.build());
+      }
+      bitField0_ |= 0x00000008;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder mergePrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (((bitField0_ & 0x00000008) != 0)
+            && precommitToken_ != null
+            && precommitToken_
+                != com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()) {
+          getPrecommitTokenBuilder().mergeFrom(value);
+        } else {
+          precommitToken_ = value;
+        }
+      } else {
+        precommitTokenBuilder_.mergeFrom(value);
+      }
+      if (precommitToken_ != null) {
+        bitField0_ |= 0x00000008;
+        onChanged();
+      }
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public Builder clearPrecommitToken() {
+      bitField0_ = (bitField0_ & ~0x00000008);
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder
+        getPrecommitTokenBuilder() {
+      bitField0_ |= 0x00000008;
+      onChanged();
+      return getPrecommitTokenFieldBuilder().getBuilder();
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+        getPrecommitTokenOrBuilder() {
+      if (precommitTokenBuilder_ != null) {
+        return precommitTokenBuilder_.getMessageOrBuilder();
+      } else {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included if the read-write transaction
+     * is on a multiplexed session.
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the
+     * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+     * </pre>
+     *
+     * <code>
+     * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     */
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        getPrecommitTokenFieldBuilder() {
+      if (precommitTokenBuilder_ == null) {
+        precommitTokenBuilder_ =
+            new com.google.protobuf.SingleFieldBuilderV3<
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+                com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>(
+                getPrecommitToken(), getParentForChildren(), isClean());
+        precommitToken_ = null;
+      }
+      return precommitTokenBuilder_;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetOrBuilder.java
index 3342ed60322..7d8601247cd 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetOrBuilder.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetOrBuilder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/result_set.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 public interface ResultSetOrBuilder
@@ -190,4 +190,57 @@ public interface ResultSetOrBuilder
    * <code>.google.spanner.v1.ResultSetStats stats = 3;</code>
    */
   com.google.spanner.v1.ResultSetStatsOrBuilder getStatsOrBuilder();
+
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  boolean hasPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   *
+   * @return The precommitToken.
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included if the read-write transaction
+   * is on a multiplexed session.
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the
+   * [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+   * </pre>
+   *
+   * <code>
+   * .google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 5 [(.google.api.field_behavior) = OPTIONAL];
+   * </code>
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder getPrecommitTokenOrBuilder();
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetProto.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetProto.java
index cab0e9c2c0d..a45bb97cd5f 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetProto.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/ResultSetProto.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/result_set.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 public final class ResultSetProto {
@@ -55,39 +55,45 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
     java.lang.String[] descriptorData = {
       "\n\"google/spanner/v1/result_set.proto\022\021go"
           + "ogle.spanner.v1\032\034google/protobuf/struct."
-          + "proto\032\"google/spanner/v1/query_plan.prot"
-          + "o\032#google/spanner/v1/transaction.proto\032\034"
-          + "google/spanner/v1/type.proto\"\237\001\n\tResultS"
-          + "et\0226\n\010metadata\030\001 \001(\0132$.google.spanner.v1"
-          + ".ResultSetMetadata\022(\n\004rows\030\002 \003(\0132\032.googl"
-          + "e.protobuf.ListValue\0220\n\005stats\030\003 \001(\0132!.go"
-          + "ogle.spanner.v1.ResultSetStats\"\321\001\n\020Parti"
-          + "alResultSet\0226\n\010metadata\030\001 \001(\0132$.google.s"
-          + "panner.v1.ResultSetMetadata\022&\n\006values\030\002 "
-          + "\003(\0132\026.google.protobuf.Value\022\025\n\rchunked_v"
-          + "alue\030\003 \001(\010\022\024\n\014resume_token\030\004 \001(\014\0220\n\005stat"
-          + "s\030\005 \001(\0132!.google.spanner.v1.ResultSetSta"
-          + "ts\"\267\001\n\021ResultSetMetadata\022/\n\010row_type\030\001 \001"
-          + "(\0132\035.google.spanner.v1.StructType\0223\n\013tra"
-          + "nsaction\030\002 \001(\0132\036.google.spanner.v1.Trans"
-          + "action\022<\n\025undeclared_parameters\030\003 \001(\0132\035."
-          + "google.spanner.v1.StructType\"\271\001\n\016ResultS"
-          + "etStats\0220\n\nquery_plan\030\001 \001(\0132\034.google.spa"
-          + "nner.v1.QueryPlan\022,\n\013query_stats\030\002 \001(\0132\027"
-          + ".google.protobuf.Struct\022\031\n\017row_count_exa"
-          + "ct\030\003 \001(\003H\000\022\037\n\025row_count_lower_bound\030\004 \001("
-          + "\003H\000B\013\n\trow_countB\264\001\n\025com.google.spanner."
-          + "v1B\016ResultSetProtoP\001Z5cloud.google.com/g"
-          + "o/spanner/apiv1/spannerpb;spannerpb\370\001\001\252\002"
-          + "\027Google.Cloud.Spanner.V1\312\002\027Google\\Cloud\\"
-          + "Spanner\\V1\352\002\032Google::Cloud::Spanner::V1b"
-          + "\006proto3"
+          + "proto\032\037google/api/field_behavior.proto\032\""
+          + "google/spanner/v1/query_plan.proto\032#goog"
+          + "le/spanner/v1/transaction.proto\032\034google/"
+          + "spanner/v1/type.proto\"\362\001\n\tResultSet\0226\n\010m"
+          + "etadata\030\001 \001(\0132$.google.spanner.v1.Result"
+          + "SetMetadata\022(\n\004rows\030\002 \003(\0132\032.google.proto"
+          + "buf.ListValue\0220\n\005stats\030\003 \001(\0132!.google.sp"
+          + "anner.v1.ResultSetStats\022Q\n\017precommit_tok"
+          + "en\030\005 \001(\01323.google.spanner.v1.Multiplexed"
+          + "SessionPrecommitTokenB\003\340A\001\"\244\002\n\020PartialRe"
+          + "sultSet\0226\n\010metadata\030\001 \001(\0132$.google.spann"
+          + "er.v1.ResultSetMetadata\022&\n\006values\030\002 \003(\0132"
+          + "\026.google.protobuf.Value\022\025\n\rchunked_value"
+          + "\030\003 \001(\010\022\024\n\014resume_token\030\004 \001(\014\0220\n\005stats\030\005 "
+          + "\001(\0132!.google.spanner.v1.ResultSetStats\022Q"
+          + "\n\017precommit_token\030\010 \001(\01323.google.spanner"
+          + ".v1.MultiplexedSessionPrecommitTokenB\003\340A"
+          + "\001\"\267\001\n\021ResultSetMetadata\022/\n\010row_type\030\001 \001("
+          + "\0132\035.google.spanner.v1.StructType\0223\n\013tran"
+          + "saction\030\002 \001(\0132\036.google.spanner.v1.Transa"
+          + "ction\022<\n\025undeclared_parameters\030\003 \001(\0132\035.g"
+          + "oogle.spanner.v1.StructType\"\271\001\n\016ResultSe"
+          + "tStats\0220\n\nquery_plan\030\001 \001(\0132\034.google.span"
+          + "ner.v1.QueryPlan\022,\n\013query_stats\030\002 \001(\0132\027."
+          + "google.protobuf.Struct\022\031\n\017row_count_exac"
+          + "t\030\003 \001(\003H\000\022\037\n\025row_count_lower_bound\030\004 \001(\003"
+          + "H\000B\013\n\trow_countB\264\001\n\025com.google.spanner.v"
+          + "1B\016ResultSetProtoP\001Z5cloud.google.com/go"
+          + "/spanner/apiv1/spannerpb;spannerpb\370\001\001\252\002\027"
+          + "Google.Cloud.Spanner.V1\312\002\027Google\\Cloud\\S"
+          + "panner\\V1\352\002\032Google::Cloud::Spanner::V1b\006"
+          + "proto3"
     };
     descriptor =
         com.google.protobuf.Descriptors.FileDescriptor.internalBuildGeneratedFileFrom(
             descriptorData,
             new com.google.protobuf.Descriptors.FileDescriptor[] {
               com.google.protobuf.StructProto.getDescriptor(),
+              com.google.api.FieldBehaviorProto.getDescriptor(),
               com.google.spanner.v1.QueryPlanProto.getDescriptor(),
               com.google.spanner.v1.TransactionProto.getDescriptor(),
               com.google.spanner.v1.TypeProto.getDescriptor(),
@@ -98,7 +104,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
         new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
             internal_static_google_spanner_v1_ResultSet_descriptor,
             new java.lang.String[] {
-              "Metadata", "Rows", "Stats",
+              "Metadata", "Rows", "Stats", "PrecommitToken",
             });
     internal_static_google_spanner_v1_PartialResultSet_descriptor =
         getDescriptor().getMessageTypes().get(1);
@@ -106,7 +112,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
         new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
             internal_static_google_spanner_v1_PartialResultSet_descriptor,
             new java.lang.String[] {
-              "Metadata", "Values", "ChunkedValue", "ResumeToken", "Stats",
+              "Metadata", "Values", "ChunkedValue", "ResumeToken", "Stats", "PrecommitToken",
             });
     internal_static_google_spanner_v1_ResultSetMetadata_descriptor =
         getDescriptor().getMessageTypes().get(2);
@@ -124,7 +130,13 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
             new java.lang.String[] {
               "QueryPlan", "QueryStats", "RowCountExact", "RowCountLowerBound", "RowCount",
             });
+    com.google.protobuf.ExtensionRegistry registry =
+        com.google.protobuf.ExtensionRegistry.newInstance();
+    registry.add(com.google.api.FieldBehaviorProto.fieldBehavior);
+    com.google.protobuf.Descriptors.FileDescriptor.internalUpdateFileDescriptor(
+        descriptor, registry);
     com.google.protobuf.StructProto.getDescriptor();
+    com.google.api.FieldBehaviorProto.getDescriptor();
     com.google.spanner.v1.QueryPlanProto.getDescriptor();
     com.google.spanner.v1.TransactionProto.getDescriptor();
     com.google.spanner.v1.TypeProto.getDescriptor();
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/SpannerProto.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/SpannerProto.java
index a2b7ea2625e..0badef8d708 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/SpannerProto.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/SpannerProto.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/spanner.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 public final class SpannerProto {
@@ -271,167 +271,172 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
           + "(\0132C.google.spanner.v1.ExecuteBatchDmlRe"
           + "quest.Statement.ParamTypesEntry\032J\n\017Param"
           + "TypesEntry\022\013\n\003key\030\001 \001(\t\022&\n\005value\030\002 \001(\0132\027"
-          + ".google.spanner.v1.Type:\0028\001\"p\n\027ExecuteBa"
-          + "tchDmlResponse\0221\n\013result_sets\030\001 \003(\0132\034.go"
-          + "ogle.spanner.v1.ResultSet\022\"\n\006status\030\002 \001("
-          + "\0132\022.google.rpc.Status\"H\n\020PartitionOption"
-          + "s\022\034\n\024partition_size_bytes\030\001 \001(\003\022\026\n\016max_p"
-          + "artitions\030\002 \001(\003\"\243\003\n\025PartitionQueryReques"
-          + "t\0227\n\007session\030\001 \001(\tB&\340A\002\372A \n\036spanner.goog"
-          + "leapis.com/Session\022;\n\013transaction\030\002 \001(\0132"
-          + "&.google.spanner.v1.TransactionSelector\022"
-          + "\020\n\003sql\030\003 \001(\tB\003\340A\002\022\'\n\006params\030\004 \001(\0132\027.goog"
-          + "le.protobuf.Struct\022M\n\013param_types\030\005 \003(\0132"
-          + "8.google.spanner.v1.PartitionQueryReques"
-          + "t.ParamTypesEntry\022>\n\021partition_options\030\006"
-          + " \001(\0132#.google.spanner.v1.PartitionOption"
-          + "s\032J\n\017ParamTypesEntry\022\013\n\003key\030\001 \001(\t\022&\n\005val"
-          + "ue\030\002 \001(\0132\027.google.spanner.v1.Type:\0028\001\"\261\002"
-          + "\n\024PartitionReadRequest\0227\n\007session\030\001 \001(\tB"
-          + "&\340A\002\372A \n\036spanner.googleapis.com/Session\022"
-          + ";\n\013transaction\030\002 \001(\0132&.google.spanner.v1"
-          + ".TransactionSelector\022\022\n\005table\030\003 \001(\tB\003\340A\002"
-          + "\022\r\n\005index\030\004 \001(\t\022\017\n\007columns\030\005 \003(\t\022/\n\007key_"
-          + "set\030\006 \001(\0132\031.google.spanner.v1.KeySetB\003\340A"
-          + "\002\022>\n\021partition_options\030\t \001(\0132#.google.sp"
-          + "anner.v1.PartitionOptions\"$\n\tPartition\022\027"
-          + "\n\017partition_token\030\001 \001(\014\"z\n\021PartitionResp"
-          + "onse\0220\n\npartitions\030\001 \003(\0132\034.google.spanne"
-          + "r.v1.Partition\0223\n\013transaction\030\002 \001(\0132\036.go"
-          + "ogle.spanner.v1.Transaction\"\366\005\n\013ReadRequ"
-          + "est\0227\n\007session\030\001 \001(\tB&\340A\002\372A \n\036spanner.go"
-          + "ogleapis.com/Session\022;\n\013transaction\030\002 \001("
-          + "\0132&.google.spanner.v1.TransactionSelecto"
-          + "r\022\022\n\005table\030\003 \001(\tB\003\340A\002\022\r\n\005index\030\004 \001(\t\022\024\n\007"
-          + "columns\030\005 \003(\tB\003\340A\002\022/\n\007key_set\030\006 \001(\0132\031.go"
-          + "ogle.spanner.v1.KeySetB\003\340A\002\022\r\n\005limit\030\010 \001"
-          + "(\003\022\024\n\014resume_token\030\t \001(\014\022\027\n\017partition_to"
-          + "ken\030\n \001(\014\022:\n\017request_options\030\013 \001(\0132!.goo"
-          + "gle.spanner.v1.RequestOptions\022E\n\025directe"
-          + "d_read_options\030\016 \001(\0132&.google.spanner.v1"
-          + ".DirectedReadOptions\022\032\n\022data_boost_enabl"
-          + "ed\030\017 \001(\010\022=\n\010order_by\030\020 \001(\0162&.google.span"
-          + "ner.v1.ReadRequest.OrderByB\003\340A\001\022?\n\tlock_"
-          + "hint\030\021 \001(\0162\'.google.spanner.v1.ReadReque"
-          + "st.LockHintB\003\340A\001\"T\n\007OrderBy\022\030\n\024ORDER_BY_"
-          + "UNSPECIFIED\020\000\022\030\n\024ORDER_BY_PRIMARY_KEY\020\001\022"
-          + "\025\n\021ORDER_BY_NO_ORDER\020\002\"T\n\010LockHint\022\031\n\025LO"
-          + "CK_HINT_UNSPECIFIED\020\000\022\024\n\020LOCK_HINT_SHARE"
-          + "D\020\001\022\027\n\023LOCK_HINT_EXCLUSIVE\020\002\"\313\001\n\027BeginTr"
-          + "ansactionRequest\0227\n\007session\030\001 \001(\tB&\340A\002\372A"
-          + " \n\036spanner.googleapis.com/Session\022;\n\007opt"
-          + "ions\030\002 \001(\0132%.google.spanner.v1.Transacti"
-          + "onOptionsB\003\340A\002\022:\n\017request_options\030\003 \001(\0132"
-          + "!.google.spanner.v1.RequestOptions\"\375\002\n\rC"
-          + "ommitRequest\0227\n\007session\030\001 \001(\tB&\340A\002\372A \n\036s"
-          + "panner.googleapis.com/Session\022\030\n\016transac"
-          + "tion_id\030\002 \001(\014H\000\022G\n\026single_use_transactio"
-          + "n\030\003 \001(\0132%.google.spanner.v1.TransactionO"
-          + "ptionsH\000\022.\n\tmutations\030\004 \003(\0132\033.google.spa"
-          + "nner.v1.Mutation\022\033\n\023return_commit_stats\030"
-          + "\005 \001(\010\0228\n\020max_commit_delay\030\010 \001(\0132\031.google"
-          + ".protobuf.DurationB\003\340A\001\022:\n\017request_optio"
-          + "ns\030\006 \001(\0132!.google.spanner.v1.RequestOpti"
-          + "onsB\r\n\013transaction\"g\n\017RollbackRequest\0227\n"
-          + "\007session\030\001 \001(\tB&\340A\002\372A \n\036spanner.googleap"
-          + "is.com/Session\022\033\n\016transaction_id\030\002 \001(\014B\003"
-          + "\340A\002\"\316\002\n\021BatchWriteRequest\0227\n\007session\030\001 \001"
-          + "(\tB&\340A\002\372A \n\036spanner.googleapis.com/Sessi"
-          + "on\022:\n\017request_options\030\003 \001(\0132!.google.spa"
-          + "nner.v1.RequestOptions\022P\n\017mutation_group"
-          + "s\030\004 \003(\01322.google.spanner.v1.BatchWriteRe"
-          + "quest.MutationGroupB\003\340A\002\022,\n\037exclude_txn_"
-          + "from_change_streams\030\005 \001(\010B\003\340A\001\032D\n\rMutati"
-          + "onGroup\0223\n\tmutations\030\001 \003(\0132\033.google.span"
-          + "ner.v1.MutationB\003\340A\002\"\177\n\022BatchWriteRespon"
-          + "se\022\017\n\007indexes\030\001 \003(\005\022\"\n\006status\030\002 \001(\0132\022.go"
-          + "ogle.rpc.Status\0224\n\020commit_timestamp\030\003 \001("
-          + "\0132\032.google.protobuf.Timestamp2\213\030\n\007Spanne"
-          + "r\022\246\001\n\rCreateSession\022\'.google.spanner.v1."
-          + "CreateSessionRequest\032\032.google.spanner.v1"
-          + ".Session\"P\332A\010database\202\323\344\223\002?\":/v1/{databa"
-          + "se=projects/*/instances/*/databases/*}/s"
-          + "essions:\001*\022\340\001\n\023BatchCreateSessions\022-.goo"
-          + "gle.spanner.v1.BatchCreateSessionsReques"
-          + "t\032..google.spanner.v1.BatchCreateSession"
-          + "sResponse\"j\332A\026database,session_count\202\323\344\223"
-          + "\002K\"F/v1/{database=projects/*/instances/*"
-          + "/databases/*}/sessions:batchCreate:\001*\022\227\001"
-          + "\n\nGetSession\022$.google.spanner.v1.GetSess"
-          + "ionRequest\032\032.google.spanner.v1.Session\"G"
-          + "\332A\004name\202\323\344\223\002:\0228/v1/{name=projects/*/inst"
-          + "ances/*/databases/*/sessions/*}\022\256\001\n\014List"
-          + "Sessions\022&.google.spanner.v1.ListSession"
-          + "sRequest\032\'.google.spanner.v1.ListSession"
-          + "sResponse\"M\332A\010database\202\323\344\223\002<\022:/v1/{datab"
-          + "ase=projects/*/instances/*/databases/*}/"
-          + "sessions\022\231\001\n\rDeleteSession\022\'.google.span"
-          + "ner.v1.DeleteSessionRequest\032\026.google.pro"
-          + "tobuf.Empty\"G\332A\004name\202\323\344\223\002:*8/v1/{name=pr"
-          + "ojects/*/instances/*/databases/*/session"
-          + "s/*}\022\243\001\n\nExecuteSql\022$.google.spanner.v1."
-          + "ExecuteSqlRequest\032\034.google.spanner.v1.Re"
-          + "sultSet\"Q\202\323\344\223\002K\"F/v1/{session=projects/*"
-          + "/instances/*/databases/*/sessions/*}:exe"
-          + "cuteSql:\001*\022\276\001\n\023ExecuteStreamingSql\022$.goo"
-          + "gle.spanner.v1.ExecuteSqlRequest\032#.googl"
-          + "e.spanner.v1.PartialResultSet\"Z\202\323\344\223\002T\"O/"
-          + "v1/{session=projects/*/instances/*/datab"
-          + "ases/*/sessions/*}:executeStreamingSql:\001"
-          + "*0\001\022\300\001\n\017ExecuteBatchDml\022).google.spanner"
-          + ".v1.ExecuteBatchDmlRequest\032*.google.span"
-          + "ner.v1.ExecuteBatchDmlResponse\"V\202\323\344\223\002P\"K"
+          + ".google.spanner.v1.Type:\0028\001\"\303\001\n\027ExecuteB"
+          + "atchDmlResponse\0221\n\013result_sets\030\001 \003(\0132\034.g"
+          + "oogle.spanner.v1.ResultSet\022\"\n\006status\030\002 \001"
+          + "(\0132\022.google.rpc.Status\022Q\n\017precommit_toke"
+          + "n\030\003 \001(\01323.google.spanner.v1.MultiplexedS"
+          + "essionPrecommitTokenB\003\340A\001\"H\n\020PartitionOp"
+          + "tions\022\034\n\024partition_size_bytes\030\001 \001(\003\022\026\n\016m"
+          + "ax_partitions\030\002 \001(\003\"\243\003\n\025PartitionQueryRe"
+          + "quest\0227\n\007session\030\001 \001(\tB&\340A\002\372A \n\036spanner."
+          + "googleapis.com/Session\022;\n\013transaction\030\002 "
+          + "\001(\0132&.google.spanner.v1.TransactionSelec"
+          + "tor\022\020\n\003sql\030\003 \001(\tB\003\340A\002\022\'\n\006params\030\004 \001(\0132\027."
+          + "google.protobuf.Struct\022M\n\013param_types\030\005 "
+          + "\003(\01328.google.spanner.v1.PartitionQueryRe"
+          + "quest.ParamTypesEntry\022>\n\021partition_optio"
+          + "ns\030\006 \001(\0132#.google.spanner.v1.PartitionOp"
+          + "tions\032J\n\017ParamTypesEntry\022\013\n\003key\030\001 \001(\t\022&\n"
+          + "\005value\030\002 \001(\0132\027.google.spanner.v1.Type:\0028"
+          + "\001\"\261\002\n\024PartitionReadRequest\0227\n\007session\030\001 "
+          + "\001(\tB&\340A\002\372A \n\036spanner.googleapis.com/Sess"
+          + "ion\022;\n\013transaction\030\002 \001(\0132&.google.spanne"
+          + "r.v1.TransactionSelector\022\022\n\005table\030\003 \001(\tB"
+          + "\003\340A\002\022\r\n\005index\030\004 \001(\t\022\017\n\007columns\030\005 \003(\t\022/\n\007"
+          + "key_set\030\006 \001(\0132\031.google.spanner.v1.KeySet"
+          + "B\003\340A\002\022>\n\021partition_options\030\t \001(\0132#.googl"
+          + "e.spanner.v1.PartitionOptions\"$\n\tPartiti"
+          + "on\022\027\n\017partition_token\030\001 \001(\014\"z\n\021Partition"
+          + "Response\0220\n\npartitions\030\001 \003(\0132\034.google.sp"
+          + "anner.v1.Partition\0223\n\013transaction\030\002 \001(\0132"
+          + "\036.google.spanner.v1.Transaction\"\366\005\n\013Read"
+          + "Request\0227\n\007session\030\001 \001(\tB&\340A\002\372A \n\036spanne"
+          + "r.googleapis.com/Session\022;\n\013transaction\030"
+          + "\002 \001(\0132&.google.spanner.v1.TransactionSel"
+          + "ector\022\022\n\005table\030\003 \001(\tB\003\340A\002\022\r\n\005index\030\004 \001(\t"
+          + "\022\024\n\007columns\030\005 \003(\tB\003\340A\002\022/\n\007key_set\030\006 \001(\0132"
+          + "\031.google.spanner.v1.KeySetB\003\340A\002\022\r\n\005limit"
+          + "\030\010 \001(\003\022\024\n\014resume_token\030\t \001(\014\022\027\n\017partitio"
+          + "n_token\030\n \001(\014\022:\n\017request_options\030\013 \001(\0132!"
+          + ".google.spanner.v1.RequestOptions\022E\n\025dir"
+          + "ected_read_options\030\016 \001(\0132&.google.spanne"
+          + "r.v1.DirectedReadOptions\022\032\n\022data_boost_e"
+          + "nabled\030\017 \001(\010\022=\n\010order_by\030\020 \001(\0162&.google."
+          + "spanner.v1.ReadRequest.OrderByB\003\340A\001\022?\n\tl"
+          + "ock_hint\030\021 \001(\0162\'.google.spanner.v1.ReadR"
+          + "equest.LockHintB\003\340A\001\"T\n\007OrderBy\022\030\n\024ORDER"
+          + "_BY_UNSPECIFIED\020\000\022\030\n\024ORDER_BY_PRIMARY_KE"
+          + "Y\020\001\022\025\n\021ORDER_BY_NO_ORDER\020\002\"T\n\010LockHint\022\031"
+          + "\n\025LOCK_HINT_UNSPECIFIED\020\000\022\024\n\020LOCK_HINT_S"
+          + "HARED\020\001\022\027\n\023LOCK_HINT_EXCLUSIVE\020\002\"\203\002\n\027Beg"
+          + "inTransactionRequest\0227\n\007session\030\001 \001(\tB&\340"
+          + "A\002\372A \n\036spanner.googleapis.com/Session\022;\n"
+          + "\007options\030\002 \001(\0132%.google.spanner.v1.Trans"
+          + "actionOptionsB\003\340A\002\022:\n\017request_options\030\003 "
+          + "\001(\0132!.google.spanner.v1.RequestOptions\0226"
+          + "\n\014mutation_key\030\004 \001(\0132\033.google.spanner.v1"
+          + ".MutationB\003\340A\001\"\320\003\n\rCommitRequest\0227\n\007sess"
+          + "ion\030\001 \001(\tB&\340A\002\372A \n\036spanner.googleapis.co"
+          + "m/Session\022\030\n\016transaction_id\030\002 \001(\014H\000\022G\n\026s"
+          + "ingle_use_transaction\030\003 \001(\0132%.google.spa"
+          + "nner.v1.TransactionOptionsH\000\022.\n\tmutation"
+          + "s\030\004 \003(\0132\033.google.spanner.v1.Mutation\022\033\n\023"
+          + "return_commit_stats\030\005 \001(\010\0228\n\020max_commit_"
+          + "delay\030\010 \001(\0132\031.google.protobuf.DurationB\003"
+          + "\340A\001\022:\n\017request_options\030\006 \001(\0132!.google.sp"
+          + "anner.v1.RequestOptions\022Q\n\017precommit_tok"
+          + "en\030\t \001(\01323.google.spanner.v1.Multiplexed"
+          + "SessionPrecommitTokenB\003\340A\001B\r\n\013transactio"
+          + "n\"g\n\017RollbackRequest\0227\n\007session\030\001 \001(\tB&\340"
+          + "A\002\372A \n\036spanner.googleapis.com/Session\022\033\n"
+          + "\016transaction_id\030\002 \001(\014B\003\340A\002\"\316\002\n\021BatchWrit"
+          + "eRequest\0227\n\007session\030\001 \001(\tB&\340A\002\372A \n\036spann"
+          + "er.googleapis.com/Session\022:\n\017request_opt"
+          + "ions\030\003 \001(\0132!.google.spanner.v1.RequestOp"
+          + "tions\022P\n\017mutation_groups\030\004 \003(\01322.google."
+          + "spanner.v1.BatchWriteRequest.MutationGro"
+          + "upB\003\340A\002\022,\n\037exclude_txn_from_change_strea"
+          + "ms\030\005 \001(\010B\003\340A\001\032D\n\rMutationGroup\0223\n\tmutati"
+          + "ons\030\001 \003(\0132\033.google.spanner.v1.MutationB\003"
+          + "\340A\002\"\177\n\022BatchWriteResponse\022\017\n\007indexes\030\001 \003"
+          + "(\005\022\"\n\006status\030\002 \001(\0132\022.google.rpc.Status\0224"
+          + "\n\020commit_timestamp\030\003 \001(\0132\032.google.protob"
+          + "uf.Timestamp2\213\030\n\007Spanner\022\246\001\n\rCreateSessi"
+          + "on\022\'.google.spanner.v1.CreateSessionRequ"
+          + "est\032\032.google.spanner.v1.Session\"P\332A\010data"
+          + "base\202\323\344\223\002?\":/v1/{database=projects/*/ins"
+          + "tances/*/databases/*}/sessions:\001*\022\340\001\n\023Ba"
+          + "tchCreateSessions\022-.google.spanner.v1.Ba"
+          + "tchCreateSessionsRequest\032..google.spanne"
+          + "r.v1.BatchCreateSessionsResponse\"j\332A\026dat"
+          + "abase,session_count\202\323\344\223\002K\"F/v1/{database"
+          + "=projects/*/instances/*/databases/*}/ses"
+          + "sions:batchCreate:\001*\022\227\001\n\nGetSession\022$.go"
+          + "ogle.spanner.v1.GetSessionRequest\032\032.goog"
+          + "le.spanner.v1.Session\"G\332A\004name\202\323\344\223\002:\0228/v"
+          + "1/{name=projects/*/instances/*/databases"
+          + "/*/sessions/*}\022\256\001\n\014ListSessions\022&.google"
+          + ".spanner.v1.ListSessionsRequest\032\'.google"
+          + ".spanner.v1.ListSessionsResponse\"M\332A\010dat"
+          + "abase\202\323\344\223\002<\022:/v1/{database=projects/*/in"
+          + "stances/*/databases/*}/sessions\022\231\001\n\rDele"
+          + "teSession\022\'.google.spanner.v1.DeleteSess"
+          + "ionRequest\032\026.google.protobuf.Empty\"G\332A\004n"
+          + "ame\202\323\344\223\002:*8/v1/{name=projects/*/instance"
+          + "s/*/databases/*/sessions/*}\022\243\001\n\nExecuteS"
+          + "ql\022$.google.spanner.v1.ExecuteSqlRequest"
+          + "\032\034.google.spanner.v1.ResultSet\"Q\202\323\344\223\002K\"F"
           + "/v1/{session=projects/*/instances/*/data"
-          + "bases/*/sessions/*}:executeBatchDml:\001*\022\221"
-          + "\001\n\004Read\022\036.google.spanner.v1.ReadRequest\032"
-          + "\034.google.spanner.v1.ResultSet\"K\202\323\344\223\002E\"@/"
-          + "v1/{session=projects/*/instances/*/datab"
-          + "ases/*/sessions/*}:read:\001*\022\254\001\n\rStreaming"
-          + "Read\022\036.google.spanner.v1.ReadRequest\032#.g"
-          + "oogle.spanner.v1.PartialResultSet\"T\202\323\344\223\002"
-          + "N\"I/v1/{session=projects/*/instances/*/d"
-          + "atabases/*/sessions/*}:streamingRead:\001*0"
-          + "\001\022\311\001\n\020BeginTransaction\022*.google.spanner."
-          + "v1.BeginTransactionRequest\032\036.google.span"
-          + "ner.v1.Transaction\"i\332A\017session,options\202\323"
-          + "\344\223\002Q\"L/v1/{session=projects/*/instances/"
-          + "*/databases/*/sessions/*}:beginTransacti"
-          + "on:\001*\022\353\001\n\006Commit\022 .google.spanner.v1.Com"
-          + "mitRequest\032!.google.spanner.v1.CommitRes"
-          + "ponse\"\233\001\332A session,transaction_id,mutati"
-          + "ons\332A(session,single_use_transaction,mut"
-          + "ations\202\323\344\223\002G\"B/v1/{session=projects/*/in"
-          + "stances/*/databases/*/sessions/*}:commit"
-          + ":\001*\022\260\001\n\010Rollback\022\".google.spanner.v1.Rol"
-          + "lbackRequest\032\026.google.protobuf.Empty\"h\332A"
-          + "\026session,transaction_id\202\323\344\223\002I\"D/v1/{sess"
-          + "ion=projects/*/instances/*/databases/*/s"
-          + "essions/*}:rollback:\001*\022\267\001\n\016PartitionQuer"
-          + "y\022(.google.spanner.v1.PartitionQueryRequ"
-          + "est\032$.google.spanner.v1.PartitionRespons"
-          + "e\"U\202\323\344\223\002O\"J/v1/{session=projects/*/insta"
-          + "nces/*/databases/*/sessions/*}:partition"
-          + "Query:\001*\022\264\001\n\rPartitionRead\022\'.google.span"
-          + "ner.v1.PartitionReadRequest\032$.google.spa"
-          + "nner.v1.PartitionResponse\"T\202\323\344\223\002N\"I/v1/{"
-          + "session=projects/*/instances/*/databases"
-          + "/*/sessions/*}:partitionRead:\001*\022\310\001\n\nBatc"
-          + "hWrite\022$.google.spanner.v1.BatchWriteReq"
-          + "uest\032%.google.spanner.v1.BatchWriteRespo"
-          + "nse\"k\332A\027session,mutation_groups\202\323\344\223\002K\"F/"
-          + "v1/{session=projects/*/instances/*/datab"
-          + "ases/*/sessions/*}:batchWrite:\001*0\001\032w\312A\026s"
-          + "panner.googleapis.com\322A[https://www.goog"
-          + "leapis.com/auth/cloud-platform,https://w"
-          + "ww.googleapis.com/auth/spanner.dataB\221\002\n\025"
-          + "com.google.spanner.v1B\014SpannerProtoP\001Z5c"
-          + "loud.google.com/go/spanner/apiv1/spanner"
-          + "pb;spannerpb\252\002\027Google.Cloud.Spanner.V1\312\002"
-          + "\027Google\\Cloud\\Spanner\\V1\352\002\032Google::Cloud"
-          + "::Spanner::V1\352A_\n\037spanner.googleapis.com"
-          + "/Database\022<projects/{project}/instances/"
-          + "{instance}/databases/{database}P\000b\006proto"
-          + "3"
+          + "bases/*/sessions/*}:executeSql:\001*\022\276\001\n\023Ex"
+          + "ecuteStreamingSql\022$.google.spanner.v1.Ex"
+          + "ecuteSqlRequest\032#.google.spanner.v1.Part"
+          + "ialResultSet\"Z\202\323\344\223\002T\"O/v1/{session=proje"
+          + "cts/*/instances/*/databases/*/sessions/*"
+          + "}:executeStreamingSql:\001*0\001\022\300\001\n\017ExecuteBa"
+          + "tchDml\022).google.spanner.v1.ExecuteBatchD"
+          + "mlRequest\032*.google.spanner.v1.ExecuteBat"
+          + "chDmlResponse\"V\202\323\344\223\002P\"K/v1/{session=proj"
+          + "ects/*/instances/*/databases/*/sessions/"
+          + "*}:executeBatchDml:\001*\022\221\001\n\004Read\022\036.google."
+          + "spanner.v1.ReadRequest\032\034.google.spanner."
+          + "v1.ResultSet\"K\202\323\344\223\002E\"@/v1/{session=proje"
+          + "cts/*/instances/*/databases/*/sessions/*"
+          + "}:read:\001*\022\254\001\n\rStreamingRead\022\036.google.spa"
+          + "nner.v1.ReadRequest\032#.google.spanner.v1."
+          + "PartialResultSet\"T\202\323\344\223\002N\"I/v1/{session=p"
+          + "rojects/*/instances/*/databases/*/sessio"
+          + "ns/*}:streamingRead:\001*0\001\022\311\001\n\020BeginTransa"
+          + "ction\022*.google.spanner.v1.BeginTransacti"
+          + "onRequest\032\036.google.spanner.v1.Transactio"
+          + "n\"i\332A\017session,options\202\323\344\223\002Q\"L/v1/{sessio"
+          + "n=projects/*/instances/*/databases/*/ses"
+          + "sions/*}:beginTransaction:\001*\022\353\001\n\006Commit\022"
+          + " .google.spanner.v1.CommitRequest\032!.goog"
+          + "le.spanner.v1.CommitResponse\"\233\001\332A sessio"
+          + "n,transaction_id,mutations\332A(session,sin"
+          + "gle_use_transaction,mutations\202\323\344\223\002G\"B/v1"
+          + "/{session=projects/*/instances/*/databas"
+          + "es/*/sessions/*}:commit:\001*\022\260\001\n\010Rollback\022"
+          + "\".google.spanner.v1.RollbackRequest\032\026.go"
+          + "ogle.protobuf.Empty\"h\332A\026session,transact"
+          + "ion_id\202\323\344\223\002I\"D/v1/{session=projects/*/in"
+          + "stances/*/databases/*/sessions/*}:rollba"
+          + "ck:\001*\022\267\001\n\016PartitionQuery\022(.google.spanne"
+          + "r.v1.PartitionQueryRequest\032$.google.span"
+          + "ner.v1.PartitionResponse\"U\202\323\344\223\002O\"J/v1/{s"
+          + "ession=projects/*/instances/*/databases/"
+          + "*/sessions/*}:partitionQuery:\001*\022\264\001\n\rPart"
+          + "itionRead\022\'.google.spanner.v1.PartitionR"
+          + "eadRequest\032$.google.spanner.v1.Partition"
+          + "Response\"T\202\323\344\223\002N\"I/v1/{session=projects/"
+          + "*/instances/*/databases/*/sessions/*}:pa"
+          + "rtitionRead:\001*\022\310\001\n\nBatchWrite\022$.google.s"
+          + "panner.v1.BatchWriteRequest\032%.google.spa"
+          + "nner.v1.BatchWriteResponse\"k\332A\027session,m"
+          + "utation_groups\202\323\344\223\002K\"F/v1/{session=proje"
+          + "cts/*/instances/*/databases/*/sessions/*"
+          + "}:batchWrite:\001*0\001\032w\312A\026spanner.googleapis"
+          + ".com\322A[https://www.googleapis.com/auth/c"
+          + "loud-platform,https://www.googleapis.com"
+          + "/auth/spanner.dataB\221\002\n\025com.google.spanne"
+          + "r.v1B\014SpannerProtoP\001Z5cloud.google.com/g"
+          + "o/spanner/apiv1/spannerpb;spannerpb\252\002\027Go"
+          + "ogle.Cloud.Spanner.V1\312\002\027Google\\Cloud\\Spa"
+          + "nner\\V1\352\002\032Google::Cloud::Spanner::V1\352A_\n"
+          + "\037spanner.googleapis.com/Database\022<projec"
+          + "ts/{project}/instances/{instance}/databa"
+          + "ses/{database}P\000b\006proto3"
     };
     descriptor =
         com.google.protobuf.Descriptors.FileDescriptor.internalBuildGeneratedFileFrom(
@@ -637,7 +642,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
         new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
             internal_static_google_spanner_v1_ExecuteBatchDmlResponse_descriptor,
             new java.lang.String[] {
-              "ResultSets", "Status",
+              "ResultSets", "Status", "PrecommitToken",
             });
     internal_static_google_spanner_v1_PartitionOptions_descriptor =
         getDescriptor().getMessageTypes().get(13);
@@ -714,7 +719,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
         new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
             internal_static_google_spanner_v1_BeginTransactionRequest_descriptor,
             new java.lang.String[] {
-              "Session", "Options", "RequestOptions",
+              "Session", "Options", "RequestOptions", "MutationKey",
             });
     internal_static_google_spanner_v1_CommitRequest_descriptor =
         getDescriptor().getMessageTypes().get(20);
@@ -729,6 +734,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
               "ReturnCommitStats",
               "MaxCommitDelay",
               "RequestOptions",
+              "PrecommitToken",
               "Transaction",
             });
     internal_static_google_spanner_v1_RollbackRequest_descriptor =
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/Transaction.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/Transaction.java
index 7d12fa22d15..3a31c4b50c9 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/Transaction.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/Transaction.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/transaction.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 /**
@@ -154,6 +154,75 @@ public com.google.protobuf.TimestampOrBuilder getReadTimestampOrBuilder() {
         : readTimestamp_;
   }
 
+  public static final int PRECOMMIT_TOKEN_FIELD_NUMBER = 3;
+  private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included in the response of a BeginTransaction
+   * request if the read-write transaction is on a multiplexed session and
+   * a mutation_key was specified in the
+   * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+   * request for this transaction.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  @java.lang.Override
+  public boolean hasPrecommitToken() {
+    return ((bitField0_ & 0x00000002) != 0);
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included in the response of a BeginTransaction
+   * request if the read-write transaction is on a multiplexed session and
+   * a mutation_key was specified in the
+   * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+   * request for this transaction.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+   *
+   * @return The precommitToken.
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included in the response of a BeginTransaction
+   * request if the read-write transaction is on a multiplexed session and
+   * a mutation_key was specified in the
+   * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+   * request for this transaction.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+   */
+  @java.lang.Override
+  public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+      getPrecommitTokenOrBuilder() {
+    return precommitToken_ == null
+        ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+        : precommitToken_;
+  }
+
   private byte memoizedIsInitialized = -1;
 
   @java.lang.Override
@@ -174,6 +243,9 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
     if (((bitField0_ & 0x00000001) != 0)) {
       output.writeMessage(2, getReadTimestamp());
     }
+    if (((bitField0_ & 0x00000002) != 0)) {
+      output.writeMessage(3, getPrecommitToken());
+    }
     getUnknownFields().writeTo(output);
   }
 
@@ -189,6 +261,9 @@ public int getSerializedSize() {
     if (((bitField0_ & 0x00000001) != 0)) {
       size += com.google.protobuf.CodedOutputStream.computeMessageSize(2, getReadTimestamp());
     }
+    if (((bitField0_ & 0x00000002) != 0)) {
+      size += com.google.protobuf.CodedOutputStream.computeMessageSize(3, getPrecommitToken());
+    }
     size += getUnknownFields().getSerializedSize();
     memoizedSize = size;
     return size;
@@ -209,6 +284,10 @@ public boolean equals(final java.lang.Object obj) {
     if (hasReadTimestamp()) {
       if (!getReadTimestamp().equals(other.getReadTimestamp())) return false;
     }
+    if (hasPrecommitToken() != other.hasPrecommitToken()) return false;
+    if (hasPrecommitToken()) {
+      if (!getPrecommitToken().equals(other.getPrecommitToken())) return false;
+    }
     if (!getUnknownFields().equals(other.getUnknownFields())) return false;
     return true;
   }
@@ -226,6 +305,10 @@ public int hashCode() {
       hash = (37 * hash) + READ_TIMESTAMP_FIELD_NUMBER;
       hash = (53 * hash) + getReadTimestamp().hashCode();
     }
+    if (hasPrecommitToken()) {
+      hash = (37 * hash) + PRECOMMIT_TOKEN_FIELD_NUMBER;
+      hash = (53 * hash) + getPrecommitToken().hashCode();
+    }
     hash = (29 * hash) + getUnknownFields().hashCode();
     memoizedHashCode = hash;
     return hash;
@@ -366,6 +449,7 @@ private Builder(com.google.protobuf.GeneratedMessageV3.BuilderParent parent) {
     private void maybeForceBuilderInitialization() {
       if (com.google.protobuf.GeneratedMessageV3.alwaysUseFieldBuilders) {
         getReadTimestampFieldBuilder();
+        getPrecommitTokenFieldBuilder();
       }
     }
 
@@ -379,6 +463,11 @@ public Builder clear() {
         readTimestampBuilder_.dispose();
         readTimestampBuilder_ = null;
       }
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
       return this;
     }
 
@@ -423,6 +512,11 @@ private void buildPartial0(com.google.spanner.v1.Transaction result) {
             readTimestampBuilder_ == null ? readTimestamp_ : readTimestampBuilder_.build();
         to_bitField0_ |= 0x00000001;
       }
+      if (((from_bitField0_ & 0x00000004) != 0)) {
+        result.precommitToken_ =
+            precommitTokenBuilder_ == null ? precommitToken_ : precommitTokenBuilder_.build();
+        to_bitField0_ |= 0x00000002;
+      }
       result.bitField0_ |= to_bitField0_;
     }
 
@@ -477,6 +571,9 @@ public Builder mergeFrom(com.google.spanner.v1.Transaction other) {
       if (other.hasReadTimestamp()) {
         mergeReadTimestamp(other.getReadTimestamp());
       }
+      if (other.hasPrecommitToken()) {
+        mergePrecommitToken(other.getPrecommitToken());
+      }
       this.mergeUnknownFields(other.getUnknownFields());
       onChanged();
       return this;
@@ -515,6 +612,12 @@ public Builder mergeFrom(
                 bitField0_ |= 0x00000002;
                 break;
               } // case 18
+            case 26:
+              {
+                input.readMessage(getPrecommitTokenFieldBuilder().getBuilder(), extensionRegistry);
+                bitField0_ |= 0x00000004;
+                break;
+              } // case 26
             default:
               {
                 if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -840,6 +943,250 @@ public com.google.protobuf.TimestampOrBuilder getReadTimestampOrBuilder() {
       return readTimestampBuilder_;
     }
 
+    private com.google.spanner.v1.MultiplexedSessionPrecommitToken precommitToken_;
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        precommitTokenBuilder_;
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     *
+     * @return Whether the precommitToken field is set.
+     */
+    public boolean hasPrecommitToken() {
+      return ((bitField0_ & 0x00000004) != 0);
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     *
+     * @return The precommitToken.
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken() {
+      if (precommitTokenBuilder_ == null) {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      } else {
+        return precommitTokenBuilder_.getMessage();
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     */
+    public Builder setPrecommitToken(com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        precommitToken_ = value;
+      } else {
+        precommitTokenBuilder_.setMessage(value);
+      }
+      bitField0_ |= 0x00000004;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     */
+    public Builder setPrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder builderForValue) {
+      if (precommitTokenBuilder_ == null) {
+        precommitToken_ = builderForValue.build();
+      } else {
+        precommitTokenBuilder_.setMessage(builderForValue.build());
+      }
+      bitField0_ |= 0x00000004;
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     */
+    public Builder mergePrecommitToken(
+        com.google.spanner.v1.MultiplexedSessionPrecommitToken value) {
+      if (precommitTokenBuilder_ == null) {
+        if (((bitField0_ & 0x00000004) != 0)
+            && precommitToken_ != null
+            && precommitToken_
+                != com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()) {
+          getPrecommitTokenBuilder().mergeFrom(value);
+        } else {
+          precommitToken_ = value;
+        }
+      } else {
+        precommitTokenBuilder_.mergeFrom(value);
+      }
+      if (precommitToken_ != null) {
+        bitField0_ |= 0x00000004;
+        onChanged();
+      }
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     */
+    public Builder clearPrecommitToken() {
+      bitField0_ = (bitField0_ & ~0x00000004);
+      precommitToken_ = null;
+      if (precommitTokenBuilder_ != null) {
+        precommitTokenBuilder_.dispose();
+        precommitTokenBuilder_ = null;
+      }
+      onChanged();
+      return this;
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder
+        getPrecommitTokenBuilder() {
+      bitField0_ |= 0x00000004;
+      onChanged();
+      return getPrecommitTokenFieldBuilder().getBuilder();
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     */
+    public com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder
+        getPrecommitTokenOrBuilder() {
+      if (precommitTokenBuilder_ != null) {
+        return precommitTokenBuilder_.getMessageOrBuilder();
+      } else {
+        return precommitToken_ == null
+            ? com.google.spanner.v1.MultiplexedSessionPrecommitToken.getDefaultInstance()
+            : precommitToken_;
+      }
+    }
+    /**
+     *
+     *
+     * <pre>
+     * A precommit token will be included in the response of a BeginTransaction
+     * request if the read-write transaction is on a multiplexed session and
+     * a mutation_key was specified in the
+     * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+     * The precommit token with the highest sequence number from this transaction
+     * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+     * request for this transaction.
+     * </pre>
+     *
+     * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+     */
+    private com.google.protobuf.SingleFieldBuilderV3<
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+            com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+            com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>
+        getPrecommitTokenFieldBuilder() {
+      if (precommitTokenBuilder_ == null) {
+        precommitTokenBuilder_ =
+            new com.google.protobuf.SingleFieldBuilderV3<
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken,
+                com.google.spanner.v1.MultiplexedSessionPrecommitToken.Builder,
+                com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder>(
+                getPrecommitToken(), getParentForChildren(), isClean());
+        precommitToken_ = null;
+      }
+      return precommitTokenBuilder_;
+    }
+
     @java.lang.Override
     public final Builder setUnknownFields(final com.google.protobuf.UnknownFieldSet unknownFields) {
       return super.setUnknownFields(unknownFields);
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOptions.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOptions.java
index 60b3cdcc14a..f2acb127463 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOptions.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOptions.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/transaction.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 /**
@@ -413,6 +413,23 @@ public interface ReadWriteOrBuilder
      * @return The readLockMode.
      */
     com.google.spanner.v1.TransactionOptions.ReadWrite.ReadLockMode getReadLockMode();
+
+    /**
+     *
+     *
+     * <pre>
+     * Clients should pass the transaction ID of the previous transaction
+     * attempt that was aborted if this transaction is being executed on a
+     * multiplexed session.
+     * </pre>
+     *
+     * <code>
+     * bytes multiplexed_session_previous_transaction_id = 2 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The multiplexedSessionPreviousTransactionId.
+     */
+    com.google.protobuf.ByteString getMultiplexedSessionPreviousTransactionId();
   }
   /**
    *
@@ -436,6 +453,7 @@ private ReadWrite(com.google.protobuf.GeneratedMessageV3.Builder<?> builder) {
 
     private ReadWrite() {
       readLockMode_ = 0;
+      multiplexedSessionPreviousTransactionId_ = com.google.protobuf.ByteString.EMPTY;
     }
 
     @java.lang.Override
@@ -672,6 +690,29 @@ public com.google.spanner.v1.TransactionOptions.ReadWrite.ReadLockMode getReadLo
           : result;
     }
 
+    public static final int MULTIPLEXED_SESSION_PREVIOUS_TRANSACTION_ID_FIELD_NUMBER = 2;
+    private com.google.protobuf.ByteString multiplexedSessionPreviousTransactionId_ =
+        com.google.protobuf.ByteString.EMPTY;
+    /**
+     *
+     *
+     * <pre>
+     * Clients should pass the transaction ID of the previous transaction
+     * attempt that was aborted if this transaction is being executed on a
+     * multiplexed session.
+     * </pre>
+     *
+     * <code>
+     * bytes multiplexed_session_previous_transaction_id = 2 [(.google.api.field_behavior) = OPTIONAL];
+     * </code>
+     *
+     * @return The multiplexedSessionPreviousTransactionId.
+     */
+    @java.lang.Override
+    public com.google.protobuf.ByteString getMultiplexedSessionPreviousTransactionId() {
+      return multiplexedSessionPreviousTransactionId_;
+    }
+
     private byte memoizedIsInitialized = -1;
 
     @java.lang.Override
@@ -692,6 +733,9 @@ public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io
               .getNumber()) {
         output.writeEnum(1, readLockMode_);
       }
+      if (!multiplexedSessionPreviousTransactionId_.isEmpty()) {
+        output.writeBytes(2, multiplexedSessionPreviousTransactionId_);
+      }
       getUnknownFields().writeTo(output);
     }
 
@@ -707,6 +751,11 @@ public int getSerializedSize() {
               .getNumber()) {
         size += com.google.protobuf.CodedOutputStream.computeEnumSize(1, readLockMode_);
       }
+      if (!multiplexedSessionPreviousTransactionId_.isEmpty()) {
+        size +=
+            com.google.protobuf.CodedOutputStream.computeBytesSize(
+                2, multiplexedSessionPreviousTransactionId_);
+      }
       size += getUnknownFields().getSerializedSize();
       memoizedSize = size;
       return size;
@@ -724,6 +773,8 @@ public boolean equals(final java.lang.Object obj) {
           (com.google.spanner.v1.TransactionOptions.ReadWrite) obj;
 
       if (readLockMode_ != other.readLockMode_) return false;
+      if (!getMultiplexedSessionPreviousTransactionId()
+          .equals(other.getMultiplexedSessionPreviousTransactionId())) return false;
       if (!getUnknownFields().equals(other.getUnknownFields())) return false;
       return true;
     }
@@ -737,6 +788,8 @@ public int hashCode() {
       hash = (19 * hash) + getDescriptor().hashCode();
       hash = (37 * hash) + READ_LOCK_MODE_FIELD_NUMBER;
       hash = (53 * hash) + readLockMode_;
+      hash = (37 * hash) + MULTIPLEXED_SESSION_PREVIOUS_TRANSACTION_ID_FIELD_NUMBER;
+      hash = (53 * hash) + getMultiplexedSessionPreviousTransactionId().hashCode();
       hash = (29 * hash) + getUnknownFields().hashCode();
       memoizedHashCode = hash;
       return hash;
@@ -880,6 +933,7 @@ public Builder clear() {
         super.clear();
         bitField0_ = 0;
         readLockMode_ = 0;
+        multiplexedSessionPreviousTransactionId_ = com.google.protobuf.ByteString.EMPTY;
         return this;
       }
 
@@ -919,6 +973,10 @@ private void buildPartial0(com.google.spanner.v1.TransactionOptions.ReadWrite re
         if (((from_bitField0_ & 0x00000001) != 0)) {
           result.readLockMode_ = readLockMode_;
         }
+        if (((from_bitField0_ & 0x00000002) != 0)) {
+          result.multiplexedSessionPreviousTransactionId_ =
+              multiplexedSessionPreviousTransactionId_;
+        }
       }
 
       @java.lang.Override
@@ -972,6 +1030,11 @@ public Builder mergeFrom(com.google.spanner.v1.TransactionOptions.ReadWrite othe
         if (other.readLockMode_ != 0) {
           setReadLockModeValue(other.getReadLockModeValue());
         }
+        if (other.getMultiplexedSessionPreviousTransactionId()
+            != com.google.protobuf.ByteString.EMPTY) {
+          setMultiplexedSessionPreviousTransactionId(
+              other.getMultiplexedSessionPreviousTransactionId());
+        }
         this.mergeUnknownFields(other.getUnknownFields());
         onChanged();
         return this;
@@ -1004,6 +1067,12 @@ public Builder mergeFrom(
                   bitField0_ |= 0x00000001;
                   break;
                 } // case 8
+              case 18:
+                {
+                  multiplexedSessionPreviousTransactionId_ = input.readBytes();
+                  bitField0_ |= 0x00000002;
+                  break;
+                } // case 18
               default:
                 {
                   if (!super.parseUnknownField(input, extensionRegistry, tag)) {
@@ -1122,6 +1191,76 @@ public Builder clearReadLockMode() {
         return this;
       }
 
+      private com.google.protobuf.ByteString multiplexedSessionPreviousTransactionId_ =
+          com.google.protobuf.ByteString.EMPTY;
+      /**
+       *
+       *
+       * <pre>
+       * Clients should pass the transaction ID of the previous transaction
+       * attempt that was aborted if this transaction is being executed on a
+       * multiplexed session.
+       * </pre>
+       *
+       * <code>
+       * bytes multiplexed_session_previous_transaction_id = 2 [(.google.api.field_behavior) = OPTIONAL];
+       * </code>
+       *
+       * @return The multiplexedSessionPreviousTransactionId.
+       */
+      @java.lang.Override
+      public com.google.protobuf.ByteString getMultiplexedSessionPreviousTransactionId() {
+        return multiplexedSessionPreviousTransactionId_;
+      }
+      /**
+       *
+       *
+       * <pre>
+       * Clients should pass the transaction ID of the previous transaction
+       * attempt that was aborted if this transaction is being executed on a
+       * multiplexed session.
+       * </pre>
+       *
+       * <code>
+       * bytes multiplexed_session_previous_transaction_id = 2 [(.google.api.field_behavior) = OPTIONAL];
+       * </code>
+       *
+       * @param value The multiplexedSessionPreviousTransactionId to set.
+       * @return This builder for chaining.
+       */
+      public Builder setMultiplexedSessionPreviousTransactionId(
+          com.google.protobuf.ByteString value) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        multiplexedSessionPreviousTransactionId_ = value;
+        bitField0_ |= 0x00000002;
+        onChanged();
+        return this;
+      }
+      /**
+       *
+       *
+       * <pre>
+       * Clients should pass the transaction ID of the previous transaction
+       * attempt that was aborted if this transaction is being executed on a
+       * multiplexed session.
+       * </pre>
+       *
+       * <code>
+       * bytes multiplexed_session_previous_transaction_id = 2 [(.google.api.field_behavior) = OPTIONAL];
+       * </code>
+       *
+       * @return This builder for chaining.
+       */
+      public Builder clearMultiplexedSessionPreviousTransactionId() {
+        bitField0_ = (bitField0_ & ~0x00000002);
+        multiplexedSessionPreviousTransactionId_ =
+            getDefaultInstance().getMultiplexedSessionPreviousTransactionId();
+        onChanged();
+        return this;
+      }
+
       @java.lang.Override
       public final Builder setUnknownFields(
           final com.google.protobuf.UnknownFieldSet unknownFields) {
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOrBuilder.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOrBuilder.java
index 621c88aa4ca..5208eda515b 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOrBuilder.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionOrBuilder.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/transaction.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 public interface TransactionOrBuilder
@@ -93,4 +93,57 @@ public interface TransactionOrBuilder
    * <code>.google.protobuf.Timestamp read_timestamp = 2;</code>
    */
   com.google.protobuf.TimestampOrBuilder getReadTimestampOrBuilder();
+
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included in the response of a BeginTransaction
+   * request if the read-write transaction is on a multiplexed session and
+   * a mutation_key was specified in the
+   * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+   * request for this transaction.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+   *
+   * @return Whether the precommitToken field is set.
+   */
+  boolean hasPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included in the response of a BeginTransaction
+   * request if the read-write transaction is on a multiplexed session and
+   * a mutation_key was specified in the
+   * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+   * request for this transaction.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+   *
+   * @return The precommitToken.
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitToken getPrecommitToken();
+  /**
+   *
+   *
+   * <pre>
+   * A precommit token will be included in the response of a BeginTransaction
+   * request if the read-write transaction is on a multiplexed session and
+   * a mutation_key was specified in the
+   * [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+   * The precommit token with the highest sequence number from this transaction
+   * attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+   * request for this transaction.
+   * </pre>
+   *
+   * <code>.google.spanner.v1.MultiplexedSessionPrecommitToken precommit_token = 3;</code>
+   */
+  com.google.spanner.v1.MultiplexedSessionPrecommitTokenOrBuilder getPrecommitTokenOrBuilder();
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionProto.java b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionProto.java
index 6c0a92fbd65..a6b036013e5 100644
--- a/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionProto.java
+++ b/proto-google-cloud-spanner-v1/src/main/java/com/google/spanner/v1/TransactionProto.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2024 Google LLC
+ * Copyright 2023 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,7 +16,7 @@
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: google/spanner/v1/transaction.proto
 
-// Protobuf Java Version: 3.25.4
+// Protobuf Java Version: 3.25.3
 package com.google.spanner.v1;
 
 public final class TransactionProto {
@@ -52,6 +52,10 @@ public static void registerAllExtensions(com.google.protobuf.ExtensionRegistry r
       internal_static_google_spanner_v1_TransactionSelector_descriptor;
   static final com.google.protobuf.GeneratedMessageV3.FieldAccessorTable
       internal_static_google_spanner_v1_TransactionSelector_fieldAccessorTable;
+  static final com.google.protobuf.Descriptors.Descriptor
+      internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_descriptor;
+  static final com.google.protobuf.GeneratedMessageV3.FieldAccessorTable
+      internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_fieldAccessorTable;
 
   public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
     return descriptor;
@@ -64,37 +68,43 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
       "\n#google/spanner/v1/transaction.proto\022\021g"
           + "oogle.spanner.v1\032\036google/protobuf/durati"
           + "on.proto\032\037google/protobuf/timestamp.prot"
-          + "o\"\224\006\n\022TransactionOptions\022E\n\nread_write\030\001"
-          + " \001(\0132/.google.spanner.v1.TransactionOpti"
-          + "ons.ReadWriteH\000\022O\n\017partitioned_dml\030\003 \001(\013"
-          + "24.google.spanner.v1.TransactionOptions."
-          + "PartitionedDmlH\000\022C\n\tread_only\030\002 \001(\0132..go"
-          + "ogle.spanner.v1.TransactionOptions.ReadO"
-          + "nlyH\000\022\'\n\037exclude_txn_from_change_streams"
-          + "\030\005 \001(\010\032\262\001\n\tReadWrite\022T\n\016read_lock_mode\030\001"
-          + " \001(\0162<.google.spanner.v1.TransactionOpti"
-          + "ons.ReadWrite.ReadLockMode\"O\n\014ReadLockMo"
-          + "de\022\036\n\032READ_LOCK_MODE_UNSPECIFIED\020\000\022\017\n\013PE"
-          + "SSIMISTIC\020\001\022\016\n\nOPTIMISTIC\020\002\032\020\n\016Partition"
-          + "edDml\032\250\002\n\010ReadOnly\022\020\n\006strong\030\001 \001(\010H\000\0228\n\022"
-          + "min_read_timestamp\030\002 \001(\0132\032.google.protob"
-          + "uf.TimestampH\000\0222\n\rmax_staleness\030\003 \001(\0132\031."
-          + "google.protobuf.DurationH\000\0224\n\016read_times"
-          + "tamp\030\004 \001(\0132\032.google.protobuf.TimestampH\000"
-          + "\0224\n\017exact_staleness\030\005 \001(\0132\031.google.proto"
-          + "buf.DurationH\000\022\035\n\025return_read_timestamp\030"
-          + "\006 \001(\010B\021\n\017timestamp_boundB\006\n\004mode\"M\n\013Tran"
-          + "saction\022\n\n\002id\030\001 \001(\014\0222\n\016read_timestamp\030\002 "
-          + "\001(\0132\032.google.protobuf.Timestamp\"\244\001\n\023Tran"
-          + "sactionSelector\022;\n\nsingle_use\030\001 \001(\0132%.go"
-          + "ogle.spanner.v1.TransactionOptionsH\000\022\014\n\002"
-          + "id\030\002 \001(\014H\000\0226\n\005begin\030\003 \001(\0132%.google.spann"
-          + "er.v1.TransactionOptionsH\000B\n\n\010selectorB\263"
-          + "\001\n\025com.google.spanner.v1B\020TransactionPro"
-          + "toP\001Z5cloud.google.com/go/spanner/apiv1/"
-          + "spannerpb;spannerpb\252\002\027Google.Cloud.Spann"
-          + "er.V1\312\002\027Google\\Cloud\\Spanner\\V1\352\002\032Google"
-          + "::Cloud::Spanner::V1b\006proto3"
+          + "o\032\037google/api/field_behavior.proto\"\316\006\n\022T"
+          + "ransactionOptions\022E\n\nread_write\030\001 \001(\0132/."
+          + "google.spanner.v1.TransactionOptions.Rea"
+          + "dWriteH\000\022O\n\017partitioned_dml\030\003 \001(\01324.goog"
+          + "le.spanner.v1.TransactionOptions.Partiti"
+          + "onedDmlH\000\022C\n\tread_only\030\002 \001(\0132..google.sp"
+          + "anner.v1.TransactionOptions.ReadOnlyH\000\022\'"
+          + "\n\037exclude_txn_from_change_streams\030\005 \001(\010\032"
+          + "\354\001\n\tReadWrite\022T\n\016read_lock_mode\030\001 \001(\0162<."
+          + "google.spanner.v1.TransactionOptions.Rea"
+          + "dWrite.ReadLockMode\0228\n+multiplexed_sessi"
+          + "on_previous_transaction_id\030\002 \001(\014B\003\340A\001\"O\n"
+          + "\014ReadLockMode\022\036\n\032READ_LOCK_MODE_UNSPECIF"
+          + "IED\020\000\022\017\n\013PESSIMISTIC\020\001\022\016\n\nOPTIMISTIC\020\002\032\020"
+          + "\n\016PartitionedDml\032\250\002\n\010ReadOnly\022\020\n\006strong\030"
+          + "\001 \001(\010H\000\0228\n\022min_read_timestamp\030\002 \001(\0132\032.go"
+          + "ogle.protobuf.TimestampH\000\0222\n\rmax_stalene"
+          + "ss\030\003 \001(\0132\031.google.protobuf.DurationH\000\0224\n"
+          + "\016read_timestamp\030\004 \001(\0132\032.google.protobuf."
+          + "TimestampH\000\0224\n\017exact_staleness\030\005 \001(\0132\031.g"
+          + "oogle.protobuf.DurationH\000\022\035\n\025return_read"
+          + "_timestamp\030\006 \001(\010B\021\n\017timestamp_boundB\006\n\004m"
+          + "ode\"\233\001\n\013Transaction\022\n\n\002id\030\001 \001(\014\0222\n\016read_"
+          + "timestamp\030\002 \001(\0132\032.google.protobuf.Timest"
+          + "amp\022L\n\017precommit_token\030\003 \001(\01323.google.sp"
+          + "anner.v1.MultiplexedSessionPrecommitToke"
+          + "n\"\244\001\n\023TransactionSelector\022;\n\nsingle_use\030"
+          + "\001 \001(\0132%.google.spanner.v1.TransactionOpt"
+          + "ionsH\000\022\014\n\002id\030\002 \001(\014H\000\0226\n\005begin\030\003 \001(\0132%.go"
+          + "ogle.spanner.v1.TransactionOptionsH\000B\n\n\010"
+          + "selector\"L\n MultiplexedSessionPrecommitT"
+          + "oken\022\027\n\017precommit_token\030\001 \001(\014\022\017\n\007seq_num"
+          + "\030\002 \001(\005B\263\001\n\025com.google.spanner.v1B\020Transa"
+          + "ctionProtoP\001Z5cloud.google.com/go/spanne"
+          + "r/apiv1/spannerpb;spannerpb\252\002\027Google.Clo"
+          + "ud.Spanner.V1\312\002\027Google\\Cloud\\Spanner\\V1\352"
+          + "\002\032Google::Cloud::Spanner::V1b\006proto3"
     };
     descriptor =
         com.google.protobuf.Descriptors.FileDescriptor.internalBuildGeneratedFileFrom(
@@ -102,6 +112,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
             new com.google.protobuf.Descriptors.FileDescriptor[] {
               com.google.protobuf.DurationProto.getDescriptor(),
               com.google.protobuf.TimestampProto.getDescriptor(),
+              com.google.api.FieldBehaviorProto.getDescriptor(),
             });
     internal_static_google_spanner_v1_TransactionOptions_descriptor =
         getDescriptor().getMessageTypes().get(0);
@@ -117,7 +128,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
         new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
             internal_static_google_spanner_v1_TransactionOptions_ReadWrite_descriptor,
             new java.lang.String[] {
-              "ReadLockMode",
+              "ReadLockMode", "MultiplexedSessionPreviousTransactionId",
             });
     internal_static_google_spanner_v1_TransactionOptions_PartitionedDml_descriptor =
         internal_static_google_spanner_v1_TransactionOptions_descriptor.getNestedTypes().get(1);
@@ -145,7 +156,7 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
         new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
             internal_static_google_spanner_v1_Transaction_descriptor,
             new java.lang.String[] {
-              "Id", "ReadTimestamp",
+              "Id", "ReadTimestamp", "PrecommitToken",
             });
     internal_static_google_spanner_v1_TransactionSelector_descriptor =
         getDescriptor().getMessageTypes().get(2);
@@ -155,8 +166,22 @@ public static com.google.protobuf.Descriptors.FileDescriptor getDescriptor() {
             new java.lang.String[] {
               "SingleUse", "Id", "Begin", "Selector",
             });
+    internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_descriptor =
+        getDescriptor().getMessageTypes().get(3);
+    internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_fieldAccessorTable =
+        new com.google.protobuf.GeneratedMessageV3.FieldAccessorTable(
+            internal_static_google_spanner_v1_MultiplexedSessionPrecommitToken_descriptor,
+            new java.lang.String[] {
+              "PrecommitToken", "SeqNum",
+            });
+    com.google.protobuf.ExtensionRegistry registry =
+        com.google.protobuf.ExtensionRegistry.newInstance();
+    registry.add(com.google.api.FieldBehaviorProto.fieldBehavior);
+    com.google.protobuf.Descriptors.FileDescriptor.internalUpdateFileDescriptor(
+        descriptor, registry);
     com.google.protobuf.DurationProto.getDescriptor();
     com.google.protobuf.TimestampProto.getDescriptor();
+    com.google.api.FieldBehaviorProto.getDescriptor();
   }
 
   // @@protoc_insertion_point(outer_class_scope)
diff --git a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/commit_response.proto b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/commit_response.proto
index d44aad63b61..9e29c9ce9e0 100644
--- a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/commit_response.proto
+++ b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/commit_response.proto
@@ -17,6 +17,7 @@ syntax = "proto3";
 package google.spanner.v1;
 
 import "google/protobuf/timestamp.proto";
+import "google/spanner/v1/transaction.proto";
 
 option csharp_namespace = "Google.Cloud.Spanner.V1";
 option go_package = "cloud.google.com/go/spanner/apiv1/spannerpb;spannerpb";
@@ -47,4 +48,13 @@ message CommitResponse {
   // For more information, see
   // [CommitRequest.return_commit_stats][google.spanner.v1.CommitRequest.return_commit_stats].
   CommitStats commit_stats = 2;
+
+  // Clients should examine and retry the commit if any of the following
+  // reasons are populated.
+  oneof MultiplexedSessionRetry {
+    // If specified, transaction has not committed yet.
+    // Clients must retry the commit with the new precommit token.
+    MultiplexedSessionPrecommitToken precommit_token = 4;
+    // (-- Room left for additional retry reasons in the future. --)
+  }
 }
diff --git a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/result_set.proto b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/result_set.proto
index f392c1d7ddc..5c9b241bbff 100644
--- a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/result_set.proto
+++ b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/result_set.proto
@@ -17,6 +17,7 @@ syntax = "proto3";
 package google.spanner.v1;
 
 import "google/protobuf/struct.proto";
+import "google/api/field_behavior.proto";
 import "google/spanner/v1/query_plan.proto";
 import "google/spanner/v1/transaction.proto";
 import "google/spanner/v1/type.proto";
@@ -53,6 +54,15 @@ message ResultSet {
   // Other fields may or may not be populated, based on the
   // [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode].
   ResultSetStats stats = 3;
+
+  // A precommit token will be included if the read-write transaction
+  // is on a multiplexed session.
+  // The precommit token with the highest sequence number from this transaction
+  // attempt should be passed to the
+  // [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+  MultiplexedSessionPrecommitToken precommit_token = 5 [
+    (google.api.field_behavior) = OPTIONAL
+  ];
 }
 
 // Partial results from a streaming read or SQL query. Streaming reads and
@@ -157,6 +167,15 @@ message PartialResultSet {
   // This field will also be present in the last response for DML
   // statements.
   ResultSetStats stats = 5;
+
+  // A precommit token will be included if the read-write transaction
+  // is on a multiplexed session.
+  // The precommit token with the highest sequence number from this transaction
+  // attempt should be passed to the
+  // [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+  MultiplexedSessionPrecommitToken precommit_token = 8 [
+    (google.api.field_behavior) = OPTIONAL
+  ];
 }
 
 // Metadata about a [ResultSet][google.spanner.v1.ResultSet] or [PartialResultSet][google.spanner.v1.PartialResultSet].
diff --git a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/spanner.proto b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/spanner.proto
index 301139210ed..8720c9849f7 100644
--- a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/spanner.proto
+++ b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/spanner.proto
@@ -899,6 +899,15 @@ message ExecuteBatchDmlResponse {
   // If all DML statements are executed successfully, the status is `OK`.
   // Otherwise, the error status of the first failed statement.
   google.rpc.Status status = 2;
+
+  // A precommit token will be included if the read-write transaction
+  // is on a multiplexed session.
+  // The precommit token with the highest sequence number from this transaction
+  // attempt should be passed to the
+  // [Commit][google.spanner.v1.Spanner.Commit] request for this transaction.
+  MultiplexedSessionPrecommitToken precommit_token = 3 [
+    (google.api.field_behavior) = OPTIONAL
+  ];
 }
 
 // Options for a PartitionQueryRequest and
@@ -1215,6 +1224,14 @@ message BeginTransactionRequest {
   // transaction, set it on the reads and writes that are part of this
   // transaction instead.
   RequestOptions request_options = 3;
+
+  // Required for read-write transactions on a multiplexed session that commit
+  // mutations but do not perform any reads or queries.
+  // Clients should randomly select one of the mutations from the
+  // mutation set and send it as a part of this request.
+  Mutation mutation_key = 4 [
+    (google.api.field_behavior) = OPTIONAL
+  ];
 }
 
 // The request for [Commit][google.spanner.v1.Spanner.Commit].
@@ -1262,6 +1279,14 @@ message CommitRequest {
 
   // Common options for this request.
   RequestOptions request_options = 6;
+
+  // If the read-write transaction was executed on a multiplexed session, the
+  // precommit token with the highest sequence number received
+  // in this transaction attempt, should be included here.
+  // Failing to do so will result in a FailedPrecondition error.
+  MultiplexedSessionPrecommitToken precommit_token = 9 [
+    (google.api.field_behavior) = OPTIONAL
+  ];
 }
 
 // The request for [Rollback][google.spanner.v1.Spanner.Rollback].
diff --git a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/transaction.proto b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/transaction.proto
index 8af513d1563..0c1177c5995 100644
--- a/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/transaction.proto
+++ b/proto-google-cloud-spanner-v1/src/main/proto/google/spanner/v1/transaction.proto
@@ -18,6 +18,7 @@ package google.spanner.v1;
 
 import "google/protobuf/duration.proto";
 import "google/protobuf/timestamp.proto";
+import "google/api/field_behavior.proto";
 
 option csharp_namespace = "Google.Cloud.Spanner.V1";
 option go_package = "cloud.google.com/go/spanner/apiv1/spannerpb;spannerpb";
@@ -378,6 +379,13 @@ message TransactionOptions {
 
     // Read lock mode for the transaction.
     ReadLockMode read_lock_mode = 1;
+
+    // Clients should pass the transaction ID of the previous transaction
+    // attempt that was aborted if this transaction is being executed on a
+    // multiplexed session.
+    bytes multiplexed_session_previous_transaction_id = 2 [
+      (google.api.field_behavior) = OPTIONAL
+    ];
   }
 
   // Message type to initiate a Partitioned DML transaction.
@@ -512,6 +520,15 @@ message Transaction {
   // A timestamp in RFC3339 UTC \"Zulu\" format, accurate to nanoseconds.
   // Example: `"2014-10-02T15:01:23.045123456Z"`.
   google.protobuf.Timestamp read_timestamp = 2;
+
+  // A precommit token will be included in the response of a BeginTransaction
+  // request if the read-write transaction is on a multiplexed session and
+  // a mutation_key was specified in the
+  // [BeginTransaction][google.spanner.v1.BeginTransactionRequest].
+  // The precommit token with the highest sequence number from this transaction
+  // attempt should be passed to the [Commit][google.spanner.v1.Spanner.Commit]
+  // request for this transaction.
+  MultiplexedSessionPrecommitToken precommit_token = 3;
 }
 
 // This message is used to select the transaction in which a
@@ -539,3 +556,16 @@ message TransactionSelector {
     TransactionOptions begin = 3;
   }
 }
+
+// When a read-write transaction is executed on a multiplexed session,
+// this precommit token is sent back to the client
+// as a part of the [Transaction] message in the BeginTransaction response and
+// also as a part of the [ResultSet] and [PartialResultSet] responses.
+message MultiplexedSessionPrecommitToken {
+  // Opaque precommit token.
+  bytes precommit_token = 1;
+  // An incrementing seq number is generated on every precommit token
+  // that is returned. Clients should remember the precommit token with the
+  // highest sequence number from the current transaction attempt.
+  int32 seq_num = 2;
+}

From 0d85609b7a44999f4859d4cbee3bb9a028fde316 Mon Sep 17 00:00:00 2001
From: Sri Harsha CH <sriharshach@google.com>
Date: Fri, 20 Sep 2024 14:13:54 +0000
Subject: [PATCH 2/2] chore(spanner): add precommit token changes

---
 .../cloud/spanner/AbstractReadContext.java    | 10 ++++
 .../cloud/spanner/AbstractResultSet.java      |  3 +
 .../cloud/spanner/DatabaseClientImpl.java     |  2 +-
 .../google/cloud/spanner/GrpcResultSet.java   |  2 +-
 .../cloud/spanner/GrpcValueIterator.java      | 11 +++-
 .../MultiplexedSessionDatabaseClient.java     |  5 ++
 .../com/google/cloud/spanner/SessionImpl.java | 13 ++--
 .../cloud/spanner/TransactionRunnerImpl.java  | 60 +++++++++++++++++--
 .../cloud/spanner/GrpcResultSetTest.java      |  4 ++
 .../cloud/spanner/ReadFormatTestRunner.java   |  4 ++
 .../cloud/spanner/ResultSetsHelper.java       |  4 ++
 .../google/cloud/spanner/SessionPoolTest.java |  7 ++-
 12 files changed, 108 insertions(+), 17 deletions(-)

diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java
index caf0e06379e..270e5a2b6d9 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java
@@ -48,6 +48,7 @@
 import com.google.spanner.v1.ExecuteSqlRequest;
 import com.google.spanner.v1.ExecuteSqlRequest.QueryMode;
 import com.google.spanner.v1.ExecuteSqlRequest.QueryOptions;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.PartialResultSet;
 import com.google.spanner.v1.ReadRequest;
 import com.google.spanner.v1.RequestOptions;
@@ -878,10 +879,19 @@ String getTransactionTag() {
     return null;
   }
 
+  @Nullable
+  MultiplexedSessionPrecommitToken getLatestPrecommitToken() {
+    return null;
+  }
+
   /** This method is called when a statement returned a new transaction as part of its results. */
   @Override
   public void onTransactionMetadata(Transaction transaction, boolean shouldIncludeId) {}
 
+  /** This method is called when a response returns a new pre-commit token as part of its results. */
+  @Override
+  public void onPrecommitToken(MultiplexedSessionPrecommitToken token){}
+
   @Override
   public SpannerException onError(SpannerException e, boolean withBeginTransaction) {
     this.session.onError(e);
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractResultSet.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractResultSet.java
index 2cf93fb92ec..47067b0c0b4 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractResultSet.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractResultSet.java
@@ -27,6 +27,7 @@
 import com.google.protobuf.ListValue;
 import com.google.protobuf.ProtocolMessageEnum;
 import com.google.protobuf.Value.KindCase;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.Transaction;
 import java.io.IOException;
 import java.io.Serializable;
@@ -52,6 +53,8 @@ interface Listener {
     void onTransactionMetadata(Transaction transaction, boolean shouldIncludeId)
         throws SpannerException;
 
+    void onPrecommitToken(MultiplexedSessionPrecommitToken token);
+
     /** Called when the read finishes with an error. Returns the error that should be thrown. */
     SpannerException onError(SpannerException e, boolean withBeginTransaction);
 
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java
index 909d731818f..f0ceb72eea2 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java
@@ -241,7 +241,7 @@ public ReadOnlyTransaction readOnlyTransaction(TimestampBound bound) {
   public TransactionRunner readWriteTransaction(TransactionOption... options) {
     ISpan span = tracer.spanBuilder(READ_WRITE_TRANSACTION, options);
     try (IScope s = tracer.withSpan(span)) {
-      return getSession().readWriteTransaction(options);
+      return getMultiplexedSession().readWriteTransaction(options);
     } catch (RuntimeException e) {
       span.setStatus(e);
       span.end();
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcResultSet.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcResultSet.java
index be75c1e5c4e..23c9dd7c2d3 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcResultSet.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcResultSet.java
@@ -47,7 +47,7 @@ class GrpcResultSet extends AbstractResultSet<List<Object>> implements ProtobufR
 
   GrpcResultSet(
       CloseableIterator<PartialResultSet> iterator, Listener listener, DecodeMode decodeMode) {
-    this.iterator = new GrpcValueIterator(iterator);
+    this.iterator = new GrpcValueIterator(iterator, listener);
     this.listener = listener;
     this.decodeMode = decodeMode;
   }
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcValueIterator.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcValueIterator.java
index 0a2e17bd2b5..b78a1e1d73f 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcValueIterator.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/GrpcValueIterator.java
@@ -20,9 +20,11 @@
 import static com.google.common.base.Preconditions.checkState;
 
 import com.google.cloud.spanner.AbstractResultSet.CloseableIterator;
+import com.google.cloud.spanner.AbstractResultSet.Listener;
 import com.google.common.collect.AbstractIterator;
 import com.google.protobuf.ListValue;
 import com.google.protobuf.Value.KindCase;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.PartialResultSet;
 import com.google.spanner.v1.ResultSetMetadata;
 import com.google.spanner.v1.ResultSetStats;
@@ -44,9 +46,12 @@ private enum StreamValue {
   private PartialResultSet current;
   private int pos;
   private ResultSetStats statistics;
+  private MultiplexedSessionPrecommitToken precommitToken;
+  private final Listener listener;
 
-  GrpcValueIterator(CloseableIterator<PartialResultSet> stream) {
+  GrpcValueIterator(CloseableIterator<PartialResultSet> stream, Listener listener) {
     this.stream = stream;
+    this.listener = listener;
   }
 
   @SuppressWarnings("unchecked")
@@ -154,6 +159,10 @@ private boolean ensureReady(StreamValue requiredValue) throws SpannerException {
               ErrorCode.INTERNAL, "Invalid type metadata: " + e.getMessage(), e);
         }
       }
+      // Collect precommit token from all PartialResultSet
+      if(current.hasPrecommitToken()) {
+        listener.onPrecommitToken(current.getPrecommitToken());
+      }
       if (current.hasStats()) {
         statistics = current.getStats();
       }
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/MultiplexedSessionDatabaseClient.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/MultiplexedSessionDatabaseClient.java
index 81415e80d25..08f96b6e021 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/MultiplexedSessionDatabaseClient.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/MultiplexedSessionDatabaseClient.java
@@ -404,6 +404,11 @@ public ReadOnlyTransaction readOnlyTransaction(TimestampBound bound) {
     return createMultiplexedSessionTransaction(false).readOnlyTransaction(bound);
   }
 
+  @Override
+  public TransactionRunner readWriteTransaction(TransactionOption... options) {
+    return createMultiplexedSessionTransaction(false).readWriteTransaction(options);
+  }
+
   /**
    * It is enough with one executor to maintain the multiplexed sessions in all the clients, as they
    * do not need to be updated often, and the maintenance task is light. The core pool size is set
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java
index 7b9abc71a85..4d6acba96a7 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java
@@ -426,15 +426,18 @@ public void close() {
     }
   }
 
-  ApiFuture<ByteString> beginTransactionAsync(
-      Options transactionOptions, boolean routeToLeader, Map<SpannerRpc.Option, ?> channelHint) {
-    final SettableApiFuture<ByteString> res = SettableApiFuture.create();
+  ApiFuture<Transaction> beginTransactionAsync(
+      Options transactionOptions, boolean routeToLeader, Map<SpannerRpc.Option, ?> channelHint, com.google.spanner.v1.Mutation mutation) {
+    final SettableApiFuture<Transaction> res = SettableApiFuture.create();
     final ISpan span = tracer.spanBuilder(SpannerImpl.BEGIN_TRANSACTION);
-    final BeginTransactionRequest request =
+    BeginTransactionRequest request =
         BeginTransactionRequest.newBuilder()
             .setSession(getName())
             .setOptions(createReadWriteTransactionOptions(transactionOptions))
             .build();
+    if (sessionReference.getIsMultiplexed()) {
+      request = request.toBuilder().setMutationKey(mutation).build();
+    }
     final ApiFuture<Transaction> requestFuture;
     try (IScope ignore = tracer.withSpan(span)) {
       requestFuture = spanner.getRpc().beginTransactionAsync(request, channelHint, routeToLeader);
@@ -448,7 +451,7 @@ ApiFuture<ByteString> beginTransactionAsync(
                   ErrorCode.INTERNAL, "Missing id in transaction\n" + getName());
             }
             span.end();
-            res.set(txn.getId());
+            res.set(txn);
           } catch (ExecutionException e) {
             span.setStatus(e);
             span.end();
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java
index c8bf6dc833b..f3ec6013142 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java
@@ -46,6 +46,7 @@
 import com.google.spanner.v1.ExecuteBatchDmlResponse;
 import com.google.spanner.v1.ExecuteSqlRequest;
 import com.google.spanner.v1.ExecuteSqlRequest.QueryMode;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.RequestOptions;
 import com.google.spanner.v1.ResultSet;
 import com.google.spanner.v1.ResultSetStats;
@@ -171,6 +172,11 @@ public void removeListener(Runnable listener) {
     @GuardedBy("committingLock")
     private volatile boolean committing;
 
+    private final Object preCommitTokenLock = new Object();
+
+    @GuardedBy("preCommitTokenLock")
+    private MultiplexedSessionPrecommitToken latestPreCommitToken;
+
     @GuardedBy("lock")
     private volatile SettableApiFuture<Void> finishedAsyncOperations = SettableApiFuture.create();
 
@@ -268,7 +274,7 @@ void ensureTxn() {
     ApiFuture<Void> ensureTxnAsync() {
       final SettableApiFuture<Void> res = SettableApiFuture.create();
       if (transactionId == null || isAborted()) {
-        createTxnAsync(res);
+        createTxnAsync(res, null);
       } else {
         span.addAnnotation("Transaction Initialized", "Id", transactionId.toStringUtf8());
         txnLogger.log(
@@ -280,19 +286,23 @@ ApiFuture<Void> ensureTxnAsync() {
       return res;
     }
 
-    private void createTxnAsync(final SettableApiFuture<Void> res) {
+    private void createTxnAsync(final SettableApiFuture<Void> res, com.google.spanner.v1.Mutation mutation) {
       span.addAnnotation("Creating Transaction");
-      final ApiFuture<ByteString> fut =
-          session.beginTransactionAsync(options, isRouteToLeader(), getTransactionChannelHint());
+      final ApiFuture<Transaction> fut =
+          session.beginTransactionAsync(options, isRouteToLeader(), getTransactionChannelHint(), mutation);
       fut.addListener(
           () -> {
             try {
-              transactionId = fut.get();
+              Transaction txn = fut.get();
+              transactionId = txn.getId();
               span.addAnnotation("Transaction Creation Done", "Id", transactionId.toStringUtf8());
               txnLogger.log(
                   Level.FINER,
                   "Started transaction {0}",
                   txnLogger.isLoggable(Level.FINER) ? transactionId.asReadOnlyByteBuffer() : null);
+              if (txn.hasPrecommitToken()) {
+                onPrecommitToken(txn.getPrecommitToken());
+              }
               res.set(null);
             } catch (ExecutionException e) {
               span.addAnnotation(
@@ -370,7 +380,7 @@ ApiFuture<CommitResponse> commitAsync() {
       synchronized (lock) {
         if (transactionIdFuture == null && transactionId == null && runningAsyncOperations == 0) {
           finishOps = SettableApiFuture.create();
-          createTxnAsync(finishOps);
+          createTxnAsync(finishOps, mutationsProto.get(0));
         } else {
           finishOps = finishedAsyncOperations;
         }
@@ -423,6 +433,13 @@ public void run() {
             }
             requestBuilder.setRequestOptions(requestOptionsBuilder.build());
           }
+          if (session.getIsMultiplexed()) {
+            requestBuilder.setPrecommitToken(getLatestPrecommitToken());
+            System.out.println("setting precommit token in request");
+            System.out.println(requestBuilder.getPrecommitToken().getPrecommitToken());
+
+            txnLogger.log(Level.ALL, "setting  precommit token to commit "+requestBuilder.getPrecommitToken().getPrecommitToken());
+          }
           final CommitRequest commitRequest = requestBuilder.build();
           span.addAnnotation("Starting Commit");
           final ApiFuture<com.google.spanner.v1.CommitResponse> commitFuture;
@@ -625,6 +642,17 @@ public void onTransactionMetadata(Transaction transaction, boolean shouldInclude
       }
     }
 
+    public void onPrecommitToken(MultiplexedSessionPrecommitToken token){
+      if(token == null) return;
+      synchronized (preCommitTokenLock) {
+        if (this.latestPreCommitToken == null || token.getSeqNum() > this.latestPreCommitToken.getSeqNum()) {
+          this.latestPreCommitToken = token;
+          System.out.println("Updating precommit token to "+this.latestPreCommitToken);
+          txnLogger.log(Level.ALL, "Updating precommit token to "+this.latestPreCommitToken);
+        }
+      }
+    }
+
     @Nullable
     String getTransactionTag() {
       if (this.options.hasTag()) {
@@ -633,6 +661,13 @@ String getTransactionTag() {
       return null;
     }
 
+    @Nullable
+    MultiplexedSessionPrecommitToken getLatestPrecommitToken() {
+      synchronized (preCommitTokenLock) {
+        return this.latestPreCommitToken;
+      }
+    }
+
     @Override
     public SpannerException onError(SpannerException e, boolean withBeginTransaction) {
       e = super.onError(e, withBeginTransaction);
@@ -811,6 +846,9 @@ private ResultSet internalExecuteUpdate(
           throw new IllegalArgumentException(
               "DML response missing stats possibly due to non-DML statement as input");
         }
+        if (resultSet.hasPrecommitToken()) {
+          onPrecommitToken(resultSet.getPrecommitToken());
+        }
         return resultSet;
       } catch (Throwable t) {
         throw onError(
@@ -885,6 +923,9 @@ public ApiFuture<Long> executeUpdateAsync(Statement statement, UpdateOption... u
                       resultSet.get().getMetadata().getTransaction(),
                       builder.getTransaction().hasBegin());
                 }
+                if (resultSet.get().hasPrecommitToken()) {
+                  onPrecommitToken(resultSet.get().getPrecommitToken());
+                }
               } catch (Throwable e) {
                 // Ignore this error here as it is handled by the future that is returned by the
                 // executeUpdateAsync method.
@@ -938,6 +979,10 @@ public long[] batchUpdate(Iterable<Statement> statements, UpdateOption... update
                   response.getResultSets(i).getMetadata().getTransaction(),
                   builder.getTransaction().hasBegin());
             }
+            // TODO(harsha): check if we need to get precommit_token from response.getResultSets
+            if (response.hasPrecommitToken()) {
+              onPrecommitToken(response.getPrecommitToken());
+            }
           }
 
           // If one of the DML statements was aborted, we should throw an aborted exception.
@@ -1004,6 +1049,9 @@ public ApiFuture<long[]> batchUpdateAsync(
                           builder.getTransaction().hasBegin());
                     }
                   }
+                  if (batchDmlResponse.hasPrecommitToken()) {
+                    onPrecommitToken(batchDmlResponse.getPrecommitToken());
+                  }
                   // If one of the DML statements was aborted, we should throw an aborted exception.
                   // In all other cases, we should throw a BatchUpdateException.
                   if (batchDmlResponse.getStatus().getCode() == Code.ABORTED_VALUE) {
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/GrpcResultSetTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/GrpcResultSetTest.java
index 62336163eaf..88b9c8d21e3 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/GrpcResultSetTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/GrpcResultSetTest.java
@@ -36,6 +36,7 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.protobuf.ByteString;
 import com.google.spanner.v1.ExecuteSqlRequest.QueryMode;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.PartialResultSet;
 import com.google.spanner.v1.QueryPlan;
 import com.google.spanner.v1.ResultSetMetadata;
@@ -70,6 +71,9 @@ private static class NoOpListener implements AbstractResultSet.Listener {
     public void onTransactionMetadata(Transaction transaction, boolean shouldIncludeId)
         throws SpannerException {}
 
+    @Override
+    public void onPrecommitToken(MultiplexedSessionPrecommitToken token) {}
+
     @Override
     public SpannerException onError(SpannerException e, boolean withBeginTransaction) {
       return e;
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ReadFormatTestRunner.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ReadFormatTestRunner.java
index c973b7e471e..1044827dbc1 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ReadFormatTestRunner.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ReadFormatTestRunner.java
@@ -24,6 +24,7 @@
 import com.google.cloud.spanner.spi.v1.SpannerRpc;
 import com.google.common.io.Resources;
 import com.google.protobuf.util.JsonFormat;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.PartialResultSet;
 import com.google.spanner.v1.Transaction;
 import java.math.BigDecimal;
@@ -49,6 +50,9 @@ private static class NoOpListener implements AbstractResultSet.Listener {
     public void onTransactionMetadata(Transaction transaction, boolean shouldIncludeId)
         throws SpannerException {}
 
+    @Override
+    public void onPrecommitToken(MultiplexedSessionPrecommitToken token) {}
+
     @Override
     public SpannerException onError(SpannerException e, boolean withBeginTransaction) {
       return e;
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ResultSetsHelper.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ResultSetsHelper.java
index fc494c6f3ff..647c0b93b98 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ResultSetsHelper.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/ResultSetsHelper.java
@@ -19,6 +19,7 @@
 import com.google.cloud.spanner.AbstractResultSet.CloseableIterator;
 import com.google.cloud.spanner.AbstractResultSet.Listener;
 import com.google.protobuf.ListValue;
+import com.google.spanner.v1.MultiplexedSessionPrecommitToken;
 import com.google.spanner.v1.PartialResultSet;
 import com.google.spanner.v1.Transaction;
 import java.util.Iterator;
@@ -75,6 +76,9 @@ public PartialResultSet next() {
           public void onTransactionMetadata(Transaction transaction, boolean shouldIncludeId)
               throws SpannerException {}
 
+          @Override
+          public void onPrecommitToken(MultiplexedSessionPrecommitToken token) {}
+
           @Override
           public SpannerException onError(SpannerException e, boolean withBeginTransaction) {
             return e;
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java
index 998678e4296..becce6e0488 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java
@@ -87,6 +87,7 @@
 import com.google.spanner.v1.ExecuteSqlRequest;
 import com.google.spanner.v1.ResultSetStats;
 import com.google.spanner.v1.RollbackRequest;
+import com.google.spanner.v1.Transaction;
 import io.opencensus.metrics.LabelValue;
 import io.opencensus.metrics.MetricRegistry;
 import io.opencensus.metrics.Metrics;
@@ -1497,7 +1498,7 @@ public void testSessionNotFoundReadWriteTransaction() {
           .thenReturn(ApiFutures.immediateFuture(Empty.getDefaultInstance()));
       when(closedSession.newTransaction(Options.fromTransactionOptions()))
           .thenReturn(closedTransactionContext);
-      when(closedSession.beginTransactionAsync(any(), eq(true), any())).thenThrow(sessionNotFound);
+      when(closedSession.beginTransactionAsync(any(), eq(true), any(), any())).thenThrow(sessionNotFound);
       when(closedSession.getTracer()).thenReturn(tracer);
       TransactionRunnerImpl closedTransactionRunner = new TransactionRunnerImpl(closedSession);
       closedTransactionRunner.setSpan(span);
@@ -1512,8 +1513,8 @@ public void testSessionNotFoundReadWriteTransaction() {
       final TransactionContextImpl openTransactionContext = mock(TransactionContextImpl.class);
       when(openSession.newTransaction(Options.fromTransactionOptions()))
           .thenReturn(openTransactionContext);
-      when(openSession.beginTransactionAsync(any(), eq(true), any()))
-          .thenReturn(ApiFutures.immediateFuture(ByteString.copyFromUtf8("open-txn")));
+      when(openSession.beginTransactionAsync(any(), eq(true), any(), any()))
+          .thenReturn(ApiFutures.immediateFuture(Transaction.getDefaultInstance()));
       when(openSession.getTracer()).thenReturn(tracer);
       TransactionRunnerImpl openTransactionRunner = new TransactionRunnerImpl(openSession);
       openTransactionRunner.setSpan(span);