some schema level DDLs are not considered in dependency check

[D3Hunter]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

currently we only consider DropSchema for schema level check, but not for RecoverSchema, and there are ModifySchemaCharsetAndCollate and ModifySchemaDefaultPlacement that might need to consider too.

tidb/pkg/ddl/job_table.go

Lines 232 to 236 in 79c1499

	sql := fmt.Sprintf("select job_id from mysql.tidb_ddl_job where "+
	"(CONCAT(',', schema_ids, ',') REGEXP CONCAT(',', %s, ',') != 0 and type = %d and processing) "+
	"or (CONCAT(',', table_ids, ',') REGEXP CONCAT(',', %s, ',') != 0 and processing) "+
	"or (type = %d and processing) limit 1",
	strconv.Quote(strconv.FormatInt(job.SchemaID, 10)), model.ActionDropSchema, strconv.Quote(strconv.FormatInt(job.TableID, 10)), model.ActionFlashbackCluster)

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

master

[lance6716]

I suspect runningJobs already use unfinishedSchema to filter them. How about we remove these SQL based check? I can open a PR if you agree with it @wjhuang2016 @tangenta

[D3Hunter]

I suspect runningJobs already use unfinishedSchema to filter them. How about we remove these SQL based check? I can open a PR if you agree with it @wjhuang2016 @tangenta

i record it in the doc, the SQL based check will be removed