table: add new option DupKeyCheckMode table mutations

pkg/ddl/index.go

@@ -1646,8 +1646,6 @@ func (w *addIndexTxnWorker) batchCheckUniqueKey(txn kv.Transaction, idxRecords [
 		}
 		idxRecords[w.recordIdx[i]].skip = found && idxRecords[w.recordIdx[i]].skip
 	}
-	// Constrains is already checked.
-	w.tblCtx.GetSessionVars().StmtCtx.BatchCheck = true
 	return nil
 }
 
@@ -1841,7 +1839,12 @@ func (w *addIndexTxnWorker) BackfillData(handleRange reorgBackfillTask) (taskCtx
 			}
 
 			handle, err := w.indexes[i%len(w.indexes)].Create(
-				w.tblCtx, txn, idxRecord.vals, idxRecord.handle, idxRecord.rsData, table.WithIgnoreAssertion, table.FromBackfill)
+				w.tblCtx, txn, idxRecord.vals, idxRecord.handle, idxRecord.rsData,
+				table.WithIgnoreAssertion,
+				table.FromBackfill,
+				// Constrains is already checked in batchCheckUniqueKey
+				table.DupKeyCheckSkip,
+			)
 			if err != nil {
 				if kv.ErrKeyExists.Equal(err) && idxRecord.handle.Equal(handle) {
 					// Index already exists, skip it.

pkg/executor/admin.go

@@ -513,8 +513,6 @@ func (e *RecoverIndexExec) backfillIndexInTxn(ctx context.Context, txn kv.Transa
 		return result, err
 	}
 
-	// Constrains is already checked.
-	e.Ctx().GetSessionVars().StmtCtx.BatchCheck = true
 	for _, row := range rows {
 		if row.skip {
 			continue
@@ -526,7 +524,11 @@ func (e *RecoverIndexExec) backfillIndexInTxn(ctx context.Context, txn kv.Transa
 			return result, err
 		}
 
-		_, err = e.index.Create(e.Ctx().GetTableCtx(), txn, row.idxVals, row.handle, row.rsData, table.WithIgnoreAssertion)
+		_, err = e.index.Create(e.Ctx().GetTableCtx(), txn, row.idxVals, row.handle, row.rsData,
+			table.WithIgnoreAssertion,
+			// Constrains have already been checked.
+			table.DupKeyCheckSkip,
+		)
 		if err != nil {
 			return result, err
 		}

pkg/executor/insert.go

@@ -108,9 +108,9 @@ func (e *InsertExec) exec(ctx context.Context, rows [][]types.Datum) error {
 				if sizeHint > remain {
 					sizeHint = remain
 				}
-				err = e.addRecordWithAutoIDHint(ctx, row, sizeHint)
+				err = e.addRecordWithAutoIDHint(ctx, row, sizeHint, table.DupKeyCheckDefault)
 			} else {
-				err = e.addRecord(ctx, row)
+				err = e.addRecord(ctx, row, table.DupKeyCheckDefault)
 			}
 			if err != nil {
 				return err
@@ -282,7 +282,7 @@ func (e *InsertExec) batchUpdateDupRows(ctx context.Context, newRows [][]types.D
 		// and key-values should be filled back to dupOldRowValues for the further row check,
 		// due to there may be duplicate keys inside the insert statement.
 		if newRows[i] != nil {
-			err := e.addRecord(ctx, newRows[i])
+			err := e.addRecord(ctx, newRows[i], table.DupKeyCheckDefault)
 			if err != nil {
 				return err
 			}

pkg/executor/insert_common.go

@@ -1190,11 +1190,9 @@ func (e *InsertValues) handleDuplicateKey(ctx context.Context, txn kv.Transactio
 // All duplicate rows will be ignored and appended as duplicate warnings.
 func (e *InsertValues) batchCheckAndInsert(
 	ctx context.Context, rows [][]types.Datum,
-	addRecord func(ctx context.Context, row []types.Datum) error,
+	addRecord func(ctx context.Context, row []types.Datum, dupKeyCheck table.DupKeyCheckMode) error,
 	replace bool,
 ) error {
-	// all the rows will be checked, so it is safe to set BatchCheck = true
-	e.Ctx().GetSessionVars().StmtCtx.BatchCheck = true
 	defer tracing.StartRegion(ctx, "InsertValues.batchCheckAndInsert").End()
 	start := time.Now()
 	// Get keys need to be checked.
@@ -1307,7 +1305,8 @@ func (e *InsertValues) batchCheckAndInsert(
 		// it should be added to values map for the further row check.
 		// There may be duplicate keys inside the insert statement.
 		e.Ctx().GetSessionVars().StmtCtx.AddCopiedRows(1)
-		err = addRecord(ctx, rows[i])
+		// all the rows have been checked, so it is safe to use DupKeyCheckSkip
+		err = addRecord(ctx, rows[i], table.DupKeyCheckSkip)
 		if err != nil {
 			// throw warning when violate check constraint
 			if table.ErrCheckConstraintViolated.Equal(err) {
@@ -1405,21 +1404,21 @@ func (e *InsertValues) equalDatumsAsBinary(a []types.Datum, b []types.Datum) (bo
 	return true, nil
 }
 
-func (e *InsertValues) addRecord(ctx context.Context, row []types.Datum) error {
-	return e.addRecordWithAutoIDHint(ctx, row, 0)
+func (e *InsertValues) addRecord(ctx context.Context, row []types.Datum, dupKeyCheck table.DupKeyCheckMode) error {
+	return e.addRecordWithAutoIDHint(ctx, row, 0, dupKeyCheck)
 }
 
 func (e *InsertValues) addRecordWithAutoIDHint(
-	ctx context.Context, row []types.Datum, reserveAutoIDCount int,
+	ctx context.Context, row []types.Datum, reserveAutoIDCount int, dupKeyCheck table.DupKeyCheckMode,
 ) (err error) {
 	vars := e.Ctx().GetSessionVars()
 	if !vars.ConstraintCheckInPlace {
 		vars.PresumeKeyNotExists = true
 	}
 	if reserveAutoIDCount > 0 {
-		_, err = e.Table.AddRecord(e.Ctx().GetTableCtx(), row, table.WithCtx(ctx), table.WithReserveAutoIDHint(reserveAutoIDCount))
+		_, err = e.Table.AddRecord(e.Ctx().GetTableCtx(), row, table.WithCtx(ctx), table.WithReserveAutoIDHint(reserveAutoIDCount), dupKeyCheck)
 	} else {
-		_, err = e.Table.AddRecord(e.Ctx().GetTableCtx(), row, table.WithCtx(ctx))
+		_, err = e.Table.AddRecord(e.Ctx().GetTableCtx(), row, table.WithCtx(ctx), dupKeyCheck)
 	}
 	vars.PresumeKeyNotExists = false
 	if err != nil {
@@ -1429,7 +1428,7 @@ func (e *InsertValues) addRecordWithAutoIDHint(
 	if e.lastInsertID != 0 {
 		vars.SetLastInsertID(e.lastInsertID)
 	}
-	if !vars.StmtCtx.BatchCheck {
+	if dupKeyCheck != table.DupKeyCheckSkip {
 		for _, fkc := range e.fkChecks {
 			err = fkc.insertRowNeedToCheck(vars.StmtCtx, row)
 			if err != nil {

pkg/executor/load_data.go

@@ -655,9 +655,9 @@ func (w *commitWorker) checkAndInsertOneBatch(ctx context.Context, rows [][]type
 				if sizeHint > remain {
 					sizeHint = remain
 				}
-				err = w.addRecordWithAutoIDHint(ctx, row, sizeHint)
+				err = w.addRecordWithAutoIDHint(ctx, row, sizeHint, table.DupKeyCheckDefault)
 			} else {
-				err = w.addRecord(ctx, row)
+				err = w.addRecord(ctx, row, table.DupKeyCheckDefault)
 			}
 			if err != nil {
 				return err
@@ -670,11 +670,11 @@ func (w *commitWorker) checkAndInsertOneBatch(ctx context.Context, rows [][]type
 	}
 }
 
-func (w *commitWorker) addRecordLD(ctx context.Context, row []types.Datum) error {
+func (w *commitWorker) addRecordLD(ctx context.Context, row []types.Datum, dupKeyCheck table.DupKeyCheckMode) error {
 	if row == nil {
 		return nil
 	}
-	return w.addRecord(ctx, row)
+	return w.addRecord(ctx, row, dupKeyCheck)
 }
 
 // GetInfilePath get infile path.

pkg/executor/replace.go

@@ -24,6 +24,7 @@ import (
 	"github.com/pingcap/tidb/pkg/kv"
 	"github.com/pingcap/tidb/pkg/meta/autoid"
 	"github.com/pingcap/tidb/pkg/parser/mysql"
+	"github.com/pingcap/tidb/pkg/table"
 	"github.com/pingcap/tidb/pkg/table/tables"
 	"github.com/pingcap/tidb/pkg/tablecodec"
 	"github.com/pingcap/tidb/pkg/types"
@@ -105,7 +106,7 @@ func (e *ReplaceExec) replaceRow(ctx context.Context, r toBeCheckedRow) error {
 	}
 
 	// No duplicated rows now, insert the row.
-	err = e.addRecord(ctx, r.row)
+	err = e.addRecord(ctx, r.row, table.DupKeyCheckDefault)
 	if err != nil {
 		return err
 	}

pkg/lightning/backend/kv/base.go

@@ -208,7 +208,7 @@ func (e *BaseKVEncoder) Record2KV(record, originalRow []types.Datum, rowID int64
 
 // AddRecord adds a record into encoder
 func (e *BaseKVEncoder) AddRecord(record []types.Datum) (kv.Handle, error) {
-	return e.table.AddRecord(e.SessionCtx.GetTableCtx(), record)
+	return e.table.AddRecord(e.SessionCtx.GetTableCtx(), record, table.DupKeyCheckSkip)
 }
 
 // TableAllocators returns the allocators of the table

pkg/lightning/backend/kv/session.go

@@ -316,7 +316,6 @@ func NewSession(options *encode.SessionOptions, logger log.Logger) *Session {
 	vars := variable.NewSessionVars(s)
 	vars.SkipUTF8Check = true
 	vars.StmtCtx.InInsertStmt = true
-	vars.StmtCtx.BatchCheck = true
 	vars.SQLMode = sqlMode
 
 	typeFlags := vars.StmtCtx.TypeFlags().

pkg/sessionctx/stmtctx/stmtctx.go

@@ -194,7 +194,6 @@ type StatementContext struct {
 	contextutil.PlanCacheTracker
 	contextutil.RangeFallbackHandler
 
-	BatchCheck            bool
 	IgnoreExplainIDSuffix bool
 	MultiSchemaInfo       *model.MultiSchemaInfo
 	// If the select statement was like 'select * from t as of timestamp ...' or in a stale read transaction

pkg/table/table.go

@@ -121,7 +121,8 @@ type RecordIterFunc func(h kv.Handle, rec []types.Datum, cols []*Column) (more b
 
 // commonMutateOpt is the common options for mutating a table.
 type commonMutateOpt struct {
-	Ctx context.Context
+	Ctx         context.Context
+	DupKeyCheck DupKeyCheckMode
 }
 
 // AddRecordOpt contains the options will be used when adding a record.
@@ -222,6 +223,37 @@ func (i isUpdate) ApplyAddRecordOpt(opt *AddRecordOpt) {
 	opt.IsUpdate = true
 }
 
+// DupKeyCheckMode indicates how to check the duplicated key when adding/updating a record/index.
+type DupKeyCheckMode uint8
+
+const (
+	// DupKeyCheckDefault indicates using the default behavior.
+	// Currently, this means to use the return value `ctx.LazyCheckKeyNotExists()`.
+	// If the above method returns true, it will only check the duplicated key in the memory buffer,
+	// otherwise, it will also check the duplicated key in the storage.
+	// TODO: add `DupKeyCheckLazy` to indicate only checking the duplicated key in the memory buffer.
+	// After `DupKeyCheckLazy` added, `DupKeyCheckDefault` will be renamed to `DupKeyCheckInPlace` to force check
+	// the duplicated key in place.
+	DupKeyCheckDefault DupKeyCheckMode = iota
+	// DupKeyCheckSkip indicates skipping the duplicated key check.
+	DupKeyCheckSkip
+)
+
+// ApplyAddRecordOpt implements the AddRecordOption interface.
+func (m DupKeyCheckMode) ApplyAddRecordOpt(opt *AddRecordOpt) {
+	opt.DupKeyCheck = m
+}
+
+// ApplyUpdateRecordOpt implements the UpdateRecordOption interface.
+func (m DupKeyCheckMode) ApplyUpdateRecordOpt(opt *UpdateRecordOpt) {
+	opt.DupKeyCheck = m
+}
+
+// ApplyCreateIdxOpt implements the CreateIdxOption interface.
+func (m DupKeyCheckMode) ApplyCreateIdxOpt(opt *CreateIdxOpt) {
+	opt.DupKeyCheck = m
+}
+
 type columnAPI interface {
 	// Cols returns the columns of the table which is used in select, including hidden columns.
 	Cols() []*Column

pkg/table/tables/BUILD.bazel

@@ -77,10 +77,11 @@ go_test(
     ],
     embed = [":tables"],
     flaky = True,
-    shard_count = 31,
+    shard_count = 32,
     deps = [
         "//pkg/ddl",
         "//pkg/domain",
+        "//pkg/errctx",
         "//pkg/infoschema",
         "//pkg/kv",
         "//pkg/lightning/backend/encode",

pkg/table/tables/index.go

@@ -178,7 +178,7 @@ func (c *index) create(sctx table.MutateContext, txn kv.Transaction, indexedValu
 	}
 	vars := sctx.GetSessionVars()
 	writeBufs := sctx.GetMutateBuffers().GetWriteStmtBufs()
-	skipCheck := vars.StmtCtx.BatchCheck
+	skipCheck := opt.DupKeyCheck == table.DupKeyCheckSkip
 	evalCtx := sctx.GetExprCtx().GetEvalCtx()
 	loc, ec := evalCtx.Location(), evalCtx.ErrCtx()
 	for _, value := range indexedValues {

pkg/table/tables/tables.go

@@ -893,7 +893,7 @@ func (t *TableCommon) addRecord(sctx table.MutateContext, r []types.Datum, opt *
 	}
 	key := t.RecordKey(recordID)
 	var setPresume bool
-	if !sctx.GetSessionVars().StmtCtx.BatchCheck {
+	if opt.DupKeyCheck != table.DupKeyCheckSkip {
 		if t.meta.TempTableType != model.TempTableNone {
 			// Always check key for temporary table because it does not write to TiKV
 			_, err = txn.Get(ctx, key)
@@ -1013,7 +1013,7 @@ func genIndexKeyStrs(colVals []types.Datum) ([]string, error) {
 func (t *TableCommon) addIndices(sctx table.MutateContext, recordID kv.Handle, r []types.Datum, txn kv.Transaction, opt *table.CreateIdxOpt) (kv.Handle, error) {
 	writeBufs := sctx.GetMutateBuffers().GetWriteStmtBufs()
 	indexVals := writeBufs.IndexValsBuf
-	skipCheck := sctx.GetSessionVars().StmtCtx.BatchCheck
+	skipCheck := opt.DupKeyCheck == table.DupKeyCheckSkip
 	for _, v := range t.Indices() {
 		if !IsIndexWritable(v) {
 			continue