ddl: get latest old table ID before replace view (#53720)

pkg/ddl/BUILD.bazel

@@ -149,7 +149,6 @@ go_library(
         "//pkg/util/slice",
         "//pkg/util/sqlexec",
         "//pkg/util/stringutil",
-        "//pkg/util/syncutil",
         "//pkg/util/timeutil",
         "//pkg/util/topsql",
         "//pkg/util/topsql/state",
@@ -315,6 +314,7 @@ go_test(
         "@com_github_tikv_client_go_v2//util",
         "@io_etcd_go_etcd_client_v3//:client",
         "@org_golang_google_grpc//:grpc",
+        "@org_golang_x_sync//errgroup",
         "@org_uber_go_atomic//:atomic",
         "@org_uber_go_goleak//:goleak",
         "@org_uber_go_zap//:zap",

pkg/ddl/ddl.go

@@ -65,7 +65,6 @@ import (
 	"github.com/pingcap/tidb/pkg/util/dbterror"
 	"github.com/pingcap/tidb/pkg/util/gcutil"
 	"github.com/pingcap/tidb/pkg/util/logutil"
-	"github.com/pingcap/tidb/pkg/util/syncutil"
 	"github.com/tikv/client-go/v2/tikvrpc"
 	clientv3 "go.etcd.io/etcd/client/v3"
 	atomicutil "go.uber.org/atomic"
@@ -365,11 +364,6 @@ type ddlCtx struct {
 
 	// reorgCtx is used for reorganization.
 	reorgCtx reorgContexts
-	// backfillCtx is used for backfill workers.
-	backfillCtx struct {
-		syncutil.RWMutex
-		jobCtxMap map[int64]*JobContext
-	}
 
 	jobCtx struct {
 		sync.RWMutex

pkg/ddl/ddl_api_test.go

@@ -31,6 +31,7 @@ import (
 	"github.com/pingcap/tidb/pkg/testkit"
 	"github.com/pingcap/tidb/pkg/util/chunk"
 	"github.com/stretchr/testify/require"
+	"golang.org/x/sync/errgroup"
 )
 
 func TestGetDDLJobs(t *testing.T) {
@@ -151,6 +152,46 @@ func enQueueDDLJobs(t *testing.T, sess session.Session, txn kv.Transaction, jobT
 	}
 }
 
+func TestCreateViewConcurrently(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+
+	tk.MustExec("create table t (a int);")
+	tk.MustExec("create view v as select * from t;")
+	var (
+		counterErr error
+		counter    int
+	)
+	ddl.OnDDLCreateViewForTest = func(job *model.Job) {
+		counter++
+		if counter > 1 {
+			counterErr = fmt.Errorf("create view job should not run concurrently")
+			return
+		}
+	}
+	ddl.AfterDeliverToWorkerForTest = func(job *model.Job) {
+		if job.Type == model.ActionCreateView {
+			counter--
+		}
+	}
+	var eg errgroup.Group
+	for i := 0; i < 5; i++ {
+		eg.Go(func() error {
+			newTk := testkit.NewTestKit(t, store)
+			_, err := newTk.Exec("use test")
+			if err != nil {
+				return err
+			}
+			_, err = newTk.Exec("create or replace view v as select * from t;")
+			return err
+		})
+	}
+	err := eg.Wait()
+	require.NoError(t, err)
+	require.NoError(t, counterErr)
+}
+
 func TestCreateDropCreateTable(t *testing.T) {
 	store, dom := testkit.CreateMockStoreAndDomain(t)
 	tk := testkit.NewTestKit(t, store)

pkg/ddl/job_table.go

@@ -356,13 +356,19 @@ func (d *ddl) loadDDLJobAndRun(se *sess.Session, pool *workerPool, getJob func(*
 	d.delivery2worker(wk, pool, job)
 }
 
+// AfterDeliverToWorkerForTest is only used for test.
+var AfterDeliverToWorkerForTest func(*model.Job)
+
 // delivery2worker owns the worker, need to put it back to the pool in this function.
 func (d *ddl) delivery2worker(wk *worker, pool *workerPool, job *model.Job) {
 	injectFailPointForGetJob(job)
 	d.runningJobs.add(job)
 	d.wg.Run(func() {
 		metrics.DDLRunningJobCount.WithLabelValues(pool.tp().String()).Inc()
 		defer func() {
+			if AfterDeliverToWorkerForTest != nil {
+				AfterDeliverToWorkerForTest(job)
+			}
 			d.runningJobs.remove(job)
 			asyncNotify(d.ddlJobCh)
 			metrics.DDLRunningJobCount.WithLabelValues(pool.tp().String()).Dec()

pkg/ddl/placement_policy.go

@@ -119,7 +119,7 @@ func getPlacementPolicyByName(d *ddlCtx, t *meta.Meta, policyName model.CIStr) (
 	}
 
 	is := d.infoCache.GetLatest()
-	if is.SchemaMetaVersion() == currVer {
+	if is != nil && is.SchemaMetaVersion() == currVer {
 		// Use cached policy.
 		policy, ok := is.PolicyByName(policyName)
 		if ok {
@@ -346,7 +346,7 @@ func checkPlacementPolicyNotInUse(d *ddlCtx, t *meta.Meta, policy *model.PolicyI
 		return err
 	}
 	is := d.infoCache.GetLatest()
-	if is.SchemaMetaVersion() == currVer {
+	if is != nil && is.SchemaMetaVersion() == currVer {
 		err = CheckPlacementPolicyNotInUseFromInfoSchema(is, policy)
 	} else {
 		err = CheckPlacementPolicyNotInUseFromMeta(t, policy)

pkg/ddl/schema.go

@@ -76,7 +76,7 @@ func checkSchemaNotExists(d *ddlCtx, t *meta.Meta, schemaID int64, dbInfo *model
 		return err
 	}
 	is := d.infoCache.GetLatest()
-	if is.SchemaMetaVersion() == currVer {
+	if is != nil && is.SchemaMetaVersion() == currVer {
 		return checkSchemaNotExistsFromInfoSchema(is, schemaID, dbInfo)
 	}
 	return checkSchemaNotExistsFromStore(t, schemaID, dbInfo)

pkg/ddl/table.go

@@ -270,18 +270,28 @@ func repairTableOrViewWithCheck(t *meta.Meta, job *model.Job, schemaID int64, tb
 	return t.UpdateTable(schemaID, tbInfo)
 }
 
+// OnDDLCreateViewForTest is only used for test.
+var OnDDLCreateViewForTest func(*model.Job)
+
 func onCreateView(d *ddlCtx, t *meta.Meta, job *model.Job) (ver int64, _ error) {
 	schemaID := job.SchemaID
 	tbInfo := &model.TableInfo{}
 	var orReplace bool
-	var oldTbInfoID int64
-	if err := job.DecodeArgs(tbInfo, &orReplace, &oldTbInfoID); err != nil {
+	var _placeholder int64 // oldTblInfoID
+	if err := job.DecodeArgs(tbInfo, &orReplace, &_placeholder); err != nil {
 		// Invalid arguments, cancel this job.
 		job.State = model.JobStateCancelled
 		return ver, errors.Trace(err)
 	}
 	tbInfo.State = model.StateNone
-	err := checkTableNotExists(d, t, schemaID, tbInfo.Name.L)
+
+	oldTableID, err := findTableIDByName(d, t, schemaID, tbInfo.Name.L)
+	if infoschema.ErrTableNotExists.Equal(err) {
+		err = nil
+	}
+	if OnDDLCreateViewForTest != nil {
+		OnDDLCreateViewForTest(job)
+	}
 	if err != nil {
 		if infoschema.ErrDatabaseNotExists.Equal(err) {
 			job.State = model.JobStateCancelled
@@ -303,13 +313,13 @@ func onCreateView(d *ddlCtx, t *meta.Meta, job *model.Job) (ver int64, _ error)
 		// none -> public
 		tbInfo.State = model.StatePublic
 		tbInfo.UpdateTS = t.StartTS
-		if oldTbInfoID > 0 && orReplace {
-			err = t.DropTableOrView(schemaID, oldTbInfoID)
+		if oldTableID > 0 && orReplace {
+			err = t.DropTableOrView(schemaID, oldTableID)
 			if err != nil {
 				job.State = model.JobStateCancelled
 				return ver, errors.Trace(err)
 			}
-			err = t.GetAutoIDAccessors(schemaID, oldTbInfoID).Del()
+			err = t.GetAutoIDAccessors(schemaID, oldTableID).Del()
 			if err != nil {
 				job.State = model.JobStateCancelled
 				return ver, errors.Trace(err)
@@ -1473,7 +1483,7 @@ func checkTableNotExists(d *ddlCtx, t *meta.Meta, schemaID int64, tableName stri
 		return err
 	}
 	is := d.infoCache.GetLatest()
-	if is.SchemaMetaVersion() == currVer {
+	if is != nil && is.SchemaMetaVersion() == currVer {
 		return checkTableNotExistsFromInfoSchema(is, schemaID, tableName)
 	}
 
@@ -1526,6 +1536,48 @@ func checkTableNotExistsFromStore(t *meta.Meta, schemaID int64, tableName string
 	return nil
 }
 
+func findTableIDByName(d *ddlCtx, t *meta.Meta, schemaID int64, tableName string) (int64, error) {
+	// Try to use memory schema info to check first.
+	currVer, err := t.GetSchemaVersion()
+	if err != nil {
+		return 0, err
+	}
+	is := d.infoCache.GetLatest()
+	if is != nil && is.SchemaMetaVersion() == currVer {
+		return findTableIDFromInfoSchema(is, schemaID, tableName)
+	}
+
+	return findTableIDFromStore(t, schemaID, tableName)
+}
+
+func findTableIDFromInfoSchema(is infoschema.InfoSchema, schemaID int64, tableName string) (int64, error) {
+	schema, ok := is.SchemaByID(schemaID)
+	if !ok {
+		return 0, infoschema.ErrDatabaseNotExists.GenWithStackByArgs("")
+	}
+	tbl, err := is.TableByName(schema.Name, model.NewCIStr(tableName))
+	if err != nil {
+		return 0, err
+	}
+	return tbl.Meta().ID, nil
+}
+
+func findTableIDFromStore(t *meta.Meta, schemaID int64, tableName string) (int64, error) {
+	tbls, err := t.ListSimpleTables(schemaID)
+	if err != nil {
+		if meta.ErrDBNotExists.Equal(err) {
+			return 0, infoschema.ErrDatabaseNotExists.GenWithStackByArgs("")
+		}
+		return 0, errors.Trace(err)
+	}
+	for _, tbl := range tbls {
+		if tbl.Name.L == tableName {
+			return tbl.ID, nil
+		}
+	}
+	return 0, infoschema.ErrTableNotExists.FastGenByArgs(tableName)
+}
+
 // updateVersionAndTableInfoWithCheck checks table info validate and updates the schema version and the table information
 func updateVersionAndTableInfoWithCheck(d *ddlCtx, t *meta.Meta, job *model.Job, tblInfo *model.TableInfo, shouldUpdateVer bool, multiInfos ...schemaIDAndTableInfo) (
 	ver int64, err error) {

pkg/ddl/table_test.go

@@ -309,7 +309,8 @@ func TestCreateView(t *testing.T) {
 	}
 	ctx.SetValue(sessionctx.QueryString, "skip")
 	err = d.DoDDLJob(ctx, job)
-	require.Error(t, err)
+	// The non-existing table id in job args will not be considered anymore.
+	require.NoError(t, err)
 }
 
 func checkTableCacheTest(t *testing.T, store kv.Storage, dbInfo *model.DBInfo, tblInfo *model.TableInfo) {