Fix comments

datafusion/sql/src/planner.rs

@@ -109,7 +109,10 @@ impl ValueNormalizer {
         if self.normalize {
             crate::utils::normalize_value(&value)
         } else {
-            crate::utils::value_to_string(&value)
+            let Some(v) = crate::utils::value_to_string(&value) else {
+                return internal_err!("Value {:?} cannot be converted to string", value);
+            };
+            Ok(v)
         }
     }
 }

datafusion/sql/src/utils.rs

@@ -264,14 +264,17 @@ pub(crate) fn normalize_ident(id: Ident) -> String {
 }
 
 pub(crate) fn normalize_value(value: &Value) -> Result<String> {
-    value_to_string(value).map(|v| v.to_ascii_lowercase())
+    let Some(v) = value_to_string(value) else {
+        return plan_err!("Unsupported Value to normalize {}", value);
+    };
+    Ok(v.to_ascii_lowercase())
 }
 
-pub(crate) fn value_to_string(value: &Value) -> Result<String> {
+pub(crate) fn value_to_string(value: &Value) -> Option<String> {
     match value {
-        Value::SingleQuotedString(s) => Ok(s.to_string()),
-        Value::DollarQuotedString(s) => Ok(s.to_string()),
-        Value::Number(_, _) | Value::Boolean(_) => Ok(value.to_string()),
+        Value::SingleQuotedString(s) => Some(s.to_string()),
+        Value::DollarQuotedString(s) => Some(s.to_string()),
+        Value::Number(_, _) | Value::Boolean(_) => Some(value.to_string()),
         Value::DoubleQuotedString(_)
         | Value::EscapedStringLiteral(_)
         | Value::NationalStringLiteral(_)
@@ -287,7 +290,7 @@ pub(crate) fn value_to_string(value: &Value) -> Result<String> {
         | Value::TripleDoubleQuotedRawStringLiteral(_)
         | Value::HexStringLiteral(_)
         | Value::Null
-        | Value::Placeholder(_) => plan_err!("Unsupported Value to normalize {}", value),
+        | Value::Placeholder(_) => None,
     }
 }