ddl: do not reference owner_id for all system DDLs (#53355)

close #53327
pingcap · May 17, 2024 · 2037a2f · 2037a2f
1 parent 68db9c0
commit 2037a2f
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Showing 2 changed files with 6 additions and 14 deletions.
diff --git a/pkg/ddl/constant.go b/pkg/ddl/constant.go
@@ -25,8 +25,6 @@ const (
 	ReorgTable = "tidb_ddl_reorg"
 	// HistoryTable stores the history DDL jobs.
 	HistoryTable = "tidb_ddl_history"
-	// MDLInfoTable stores lock info used by metadata lock.
-	MDLInfoTable = "tidb_mdl_info"
 
 	// JobTableID is the table ID of `tidb_ddl_job`.
 	JobTableID = meta.MaxInt48 - 1

diff --git a/pkg/ddl/ddl_worker.go b/pkg/ddl/ddl_worker.go
@@ -37,7 +37,6 @@ import (
 	"github.com/pingcap/tidb/pkg/parser"
 	"github.com/pingcap/tidb/pkg/parser/ast"
 	"github.com/pingcap/tidb/pkg/parser/model"
-	"github.com/pingcap/tidb/pkg/parser/mysql"
 	"github.com/pingcap/tidb/pkg/parser/terror"
 	"github.com/pingcap/tidb/pkg/sessionctx"
 	"github.com/pingcap/tidb/pkg/sessionctx/binloginfo"
@@ -595,11 +594,6 @@ func (w *worker) updateDDLJob(job *model.Job, meetErr bool) error {
 	return errors.Trace(updateDDLJob2Table(w.sess, job, updateRawArgs))
 }
 
-func matchMDLInfoTable(schemaName, tblName string) bool {
-	return strings.ToLower(schemaName) == mysql.SystemDB &&
-		strings.ToLower(tblName) == MDLInfoTable
-}
-
 // registerMDLInfo registers metadata lock info.
 func (w *worker) registerMDLInfo(job *model.Job, ver int64) error {
 	if !variable.EnableMDL.Load() {
@@ -618,9 +612,9 @@ func (w *worker) registerMDLInfo(job *model.Job, ver int64) error {
 	ownerID := w.ownerManager.ID()
 	ids := rows[0].GetString(0)
 	var sql string
-	if matchMDLInfoTable(job.SchemaName, job.TableName) {
-		// DDLs that modify system table `tidb_mdl_info` could only happen in upgrade process,
-		// we should not reference 'owner_id'. Otherwise, there is a circular problem.
+	if tidbutil.IsSysDB(strings.ToLower(job.SchemaName)) {
+		// DDLs that modify system tables could only happen in upgrade process,
+		// we should not reference 'owner_id'. Otherwise, there is a circular blocking problem.
 		sql = fmt.Sprintf("replace into mysql.tidb_mdl_info (job_id, version, table_ids) values (%d, %d, '%s')", job.ID, ver, ids)
 	} else {
 		sql = fmt.Sprintf("replace into mysql.tidb_mdl_info (job_id, version, table_ids, owner_id) values (%d, %d, '%s', '%s')", job.ID, ver, ids, ownerID)
@@ -635,9 +629,9 @@ func cleanMDLInfo(pool *sess.Pool, job *model.Job, ec *clientv3.Client, ownerID
 		return
 	}
 	var sql string
-	if matchMDLInfoTable(job.SchemaName, job.TableName) {
-		// DDLs that modify system table `tidb_mdl_info` could only happen in upgrade process,
-		// we should not reference 'owner_id'. Otherwise, there is a circular problem.
+	if tidbutil.IsSysDB(strings.ToLower(job.SchemaName)) {
+		// DDLs that modify system tables could only happen in upgrade process,
+		// we should not reference 'owner_id'. Otherwise, there is a circular blocking problem.
 		sql = fmt.Sprintf("delete from mysql.tidb_mdl_info where job_id = %d", job.ID)
 	} else {
 		sql = fmt.Sprintf("delete from mysql.tidb_mdl_info where job_id = %d and owner_id = '%s'", job.ID, ownerID)