server: prefetch for DELETE and BatchPointGet when multi-statement

executor/executor.go

@@ -2127,14 +2127,7 @@ func ResetContextOfStmt(ctx sessionctx.Context, s ast.StmtNode) (err error) {
 	case *ast.UpdateStmt:
 		ResetUpdateStmtCtx(sc, stmt, vars)
 	case *ast.DeleteStmt:
-		sc.InDeleteStmt = true
-		sc.DupKeyAsWarning = stmt.IgnoreErr
-		sc.BadNullAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
-		sc.TruncateAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
-		sc.DividedByZeroAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
-		sc.AllowInvalidDate = vars.SQLMode.HasAllowInvalidDatesMode()
-		sc.IgnoreZeroInDate = !vars.SQLMode.HasNoZeroInDateMode() || !vars.SQLMode.HasNoZeroDateMode() || !vars.StrictSQLMode || stmt.IgnoreErr || sc.AllowInvalidDate
-		sc.Priority = stmt.Priority
+		ResetDeleteStmtCtx(sc, stmt, vars)
 	case *ast.InsertStmt:
 		sc.InInsertStmt = true
 		// For insert statement (not for update statement), disabling the StrictSQLMode
@@ -2275,6 +2268,18 @@ func ResetUpdateStmtCtx(sc *stmtctx.StatementContext, stmt *ast.UpdateStmt, vars
 	sc.IgnoreNoPartition = stmt.IgnoreErr
 }
 
+// ResetDeleteStmtCtx resets statement context for DeleteStmt.
+func ResetDeleteStmtCtx(sc *stmtctx.StatementContext, stmt *ast.DeleteStmt, vars *variable.SessionVars) {
+	sc.InDeleteStmt = true
+	sc.DupKeyAsWarning = stmt.IgnoreErr
+	sc.BadNullAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
+	sc.TruncateAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
+	sc.DividedByZeroAsWarning = !vars.StrictSQLMode || stmt.IgnoreErr
+	sc.AllowInvalidDate = vars.SQLMode.HasAllowInvalidDatesMode()
+	sc.IgnoreZeroInDate = !vars.SQLMode.HasNoZeroInDateMode() || !vars.SQLMode.HasNoZeroDateMode() || !vars.StrictSQLMode || stmt.IgnoreErr || sc.AllowInvalidDate
+	sc.Priority = stmt.Priority
+}
+
 func setOptionForTopSQL(sc *stmtctx.StatementContext, snapshot kv.Snapshot) {
 	if snapshot == nil {
 		return

planner/core/point_get_plan.go

@@ -328,7 +328,7 @@ type BatchPointGetPlan struct {
 	cost             float64
 
 	// SinglePart indicates whether this BatchPointGetPlan is just for a single partition, instead of the whole partition table.
-	// If the BatchPointGetPlan is built in fast path, this value if false; if the plan is generated in physical optimization for a partition,
+	// If the BatchPointGetPlan is built in fast path, this value is false; if the plan is generated in physical optimization for a partition,
 	// this value would be true. This value would decide the behavior of BatchPointGetExec, i.e, whether to compute the table ID of the partition
 	// on the fly.
 	SinglePart bool

server/conn.go

@@ -1918,6 +1918,49 @@ func (cc *clientConn) prefetchPointPlanKeys(ctx context.Context, stmts []ast.Stm
 	pointPlans := make([]plannercore.Plan, len(stmts))
 	var idxKeys []kv.Key //nolint: prealloc
 	var rowKeys []kv.Key //nolint: prealloc
+
+	handlePlan := func(p plannercore.PhysicalPlan, resetStmtCtxFn func()) error {
+		var tableID int64
+		switch v := p.(type) {
+		case *plannercore.PointGetPlan:
+			if v.PartitionInfo != nil {
+				tableID = v.PartitionInfo.ID
+			} else {
+				tableID = v.TblInfo.ID
+			}
+			if v.IndexInfo != nil {
+				resetStmtCtxFn()
+				idxKey, err1 := executor.EncodeUniqueIndexKey(cc.getCtx(), v.TblInfo, v.IndexInfo, v.IndexValues, tableID)
+				if err1 != nil {
+					return err1
+				}
+				idxKeys = append(idxKeys, idxKey)
+			} else {
+				rowKeys = append(rowKeys, tablecodec.EncodeRowKeyWithHandle(tableID, v.Handle))
+			}
+		case *plannercore.BatchPointGetPlan:
+			if v.PartitionInfos != nil {
+				// TODO: move getting physical table ID from BatchPointGetExec.initialize to newBatchPointGetPlan
+				return nil
+			}
+			if v.IndexInfo != nil {
+				resetStmtCtxFn()
+				for _, idxVals := range v.IndexValues {
+					idxKey, err1 := executor.EncodeUniqueIndexKey(cc.getCtx(), v.TblInfo, v.IndexInfo, idxVals, v.TblInfo.ID)
+					if err1 != nil {
+						return err1
+					}
+					idxKeys = append(idxKeys, idxKey)
+				}
+			} else {
+				for _, handle := range v.Handles {
+					rowKeys = append(rowKeys, tablecodec.EncodeRowKeyWithHandle(v.TblInfo.ID, handle))
+				}
+			}
+		}
+		return nil
+	}
+
 	sc := vars.StmtCtx
 	for i, stmt := range stmts {
 		if _, ok := stmt.(*ast.UseStmt); ok {
@@ -1936,25 +1979,35 @@ func (cc *clientConn) prefetchPointPlanKeys(ctx context.Context, stmts []ast.Stm
 		if p == nil {
 			continue
 		}
-		// Only support Update for now.
+		// Only support Update and Delete for now.
 		// TODO: support other point plans.
-		if x, ok := p.(*plannercore.Update); ok {
+		switch x := p.(type) {
+		case *plannercore.Update:
 			//nolint:forcetypeassert
-			updateStmt := stmt.(*ast.UpdateStmt)
-			if pp, ok := x.SelectPlan.(*plannercore.PointGetPlan); ok {
-				if pp.PartitionInfo != nil {
-					continue
-				}
-				if pp.IndexInfo != nil {
-					executor.ResetUpdateStmtCtx(sc, updateStmt, vars)
-					idxKey, err1 := executor.EncodeUniqueIndexKey(cc.getCtx(), pp.TblInfo, pp.IndexInfo, pp.IndexValues, pp.TblInfo.ID)
-					if err1 != nil {
-						return nil, err1
-					}
-					idxKeys = append(idxKeys, idxKey)
-				} else {
-					rowKeys = append(rowKeys, tablecodec.EncodeRowKeyWithHandle(pp.TblInfo.ID, pp.Handle))
-				}
+			updateStmt, ok := stmt.(*ast.UpdateStmt)
+			if !ok {
+				logutil.BgLogger().Warn("unexpected statement type for Update plan",
+					zap.String("type", fmt.Sprintf("%T", stmt)))
+				continue
+			}
+			err = handlePlan(x.SelectPlan, func() {
+				executor.ResetUpdateStmtCtx(sc, updateStmt, vars)
+			})
+			if err != nil {
+				return nil, err
+			}
+		case *plannercore.Delete:
+			deleteStmt, ok := stmt.(*ast.DeleteStmt)
+			if !ok {
+				logutil.BgLogger().Warn("unexpected statement type for Delete plan",
+					zap.String("type", fmt.Sprintf("%T", stmt)))
+				continue
+			}
+			err = handlePlan(x.SelectPlan, func() {
+				executor.ResetDeleteStmtCtx(sc, deleteStmt, vars)
+			})
+			if err != nil {
+				return nil, err
 			}
 		}
 	}

server/conn_test.go

@@ -781,7 +781,7 @@ type snapshotCache interface {
 	SnapCacheHitCount() int
 }
 
-func TestPrefetchPointKeys(t *testing.T) {
+func TestPrefetchPointKeys4Update(t *testing.T) {
 	store := testkit.CreateMockStore(t)
 
 	cc := &clientConn{
@@ -832,6 +832,137 @@ func TestPrefetchPointKeys(t *testing.T) {
 	tk.MustQuery("select * from prefetch").Check(testkit.Rows("1 1 3", "2 2 6", "3 3 5"))
 }
 
+func TestPrefetchPointKeys4Delete(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+
+	cc := &clientConn{
+		alloc:      arena.NewAllocator(1024),
+		chunkAlloc: chunk.NewAllocator(),
+		pkt: &packetIO{
+			bufWriter: bufio.NewWriter(bytes.NewBuffer(nil)),
+		},
+	}
+	tk := testkit.NewTestKit(t, store)
+	cc.setCtx(&TiDBContext{Session: tk.Session()})
+	ctx := context.Background()
+	tk.Session().GetSessionVars().EnableClusteredIndex = variable.ClusteredIndexDefModeIntOnly
+	tk.MustExec("use test")
+	tk.MustExec("create table prefetch (a int, b int, c int, primary key (a, b))")
+	tk.MustExec("insert prefetch values (1, 1, 1), (2, 2, 2), (3, 3, 3)")
+	tk.MustExec("insert prefetch values (4, 4, 4), (5, 5, 5), (6, 6, 6)")
+	tk.MustExec("begin optimistic")
+	tk.MustExec("delete from prefetch where a = 2 and b = 2")
+
+	// enable multi-statement
+	capabilities := cc.ctx.GetSessionVars().ClientCapability
+	capabilities ^= mysql.ClientMultiStatements
+	cc.ctx.SetClientCapability(capabilities)
+	query := "delete from prefetch where a = 1 and b = 1;" +
+		"delete from prefetch where a = 2 and b = 2;" +
+		"delete from prefetch where a = 3 and b = 3;"
+	err := cc.handleQuery(ctx, query)
+	require.NoError(t, err)
+	txn, err := tk.Session().Txn(false)
+	require.NoError(t, err)
+	require.True(t, txn.Valid())
+	snap := txn.GetSnapshot()
+	//nolint:forcetypeassert
+	require.Equal(t, 4, snap.(snapshotCache).SnapCacheHitCount())
+	tk.MustExec("commit")
+	tk.MustQuery("select * from prefetch").Check(testkit.Rows("4 4 4", "5 5 5", "6 6 6"))
+
+	tk.MustExec("begin pessimistic")
+	tk.MustExec("delete from prefetch where a = 5 and b = 5")
+	require.Equal(t, 2, tk.Session().GetSessionVars().TxnCtx.PessimisticCacheHit)
+	query = "delete from prefetch where a = 4 and b = 4;" +
+		"delete from prefetch where a = 5 and b = 5;" +
+		"delete from prefetch where a = 6 and b = 6;"
+	err = cc.handleQuery(ctx, query)
+	require.NoError(t, err)
+	txn, err = tk.Session().Txn(false)
+	require.NoError(t, err)
+	require.True(t, txn.Valid())
+	require.Equal(t, 6, tk.Session().GetSessionVars().TxnCtx.PessimisticCacheHit)
+	tk.MustExec("commit")
+	tk.MustQuery("select * from prefetch").Check(testkit.Rows())
+}
+
+func TestPrefetchBatchPointGet(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+
+	cc := &clientConn{
+		alloc:      arena.NewAllocator(1024),
+		chunkAlloc: chunk.NewAllocator(),
+		pkt: &packetIO{
+			bufWriter: bufio.NewWriter(bytes.NewBuffer(nil)),
+		},
+	}
+	tk := testkit.NewTestKit(t, store)
+	cc.setCtx(&TiDBContext{Session: tk.Session()})
+	ctx := context.Background()
+	tk.MustExec("use test")
+	tk.MustExec("create table prefetch (a int primary key, b int)")
+	tk.MustExec("insert prefetch values (1, 1), (2, 2), (3, 3), (4, 4), (5, 5)")
+	tk.MustExec("begin optimistic")
+	tk.MustExec("delete from prefetch where a = 1")
+
+	// enable multi-statement
+	capabilities := cc.ctx.GetSessionVars().ClientCapability
+	capabilities ^= mysql.ClientMultiStatements
+	cc.ctx.SetClientCapability(capabilities)
+	query := "delete from prefetch where a in (2,3);" +
+		"delete from prefetch where a in (4,5);"
+	err := cc.handleQuery(ctx, query)
+	require.NoError(t, err)
+	txn, err := tk.Session().Txn(false)
+	require.NoError(t, err)
+	require.True(t, txn.Valid())
+	snap := txn.GetSnapshot()
+	//nolint:forcetypeassert
+	require.Equal(t, 4, snap.(snapshotCache).SnapCacheHitCount())
+	tk.MustExec("commit")
+	tk.MustQuery("select * from prefetch").Check(testkit.Rows())
+}
+
+func TestPrefetchPartitionTable(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+
+	cc := &clientConn{
+		alloc:      arena.NewAllocator(1024),
+		chunkAlloc: chunk.NewAllocator(),
+		pkt: &packetIO{
+			bufWriter: bufio.NewWriter(bytes.NewBuffer(nil)),
+		},
+	}
+	tk := testkit.NewTestKit(t, store)
+	cc.setCtx(&TiDBContext{Session: tk.Session()})
+	ctx := context.Background()
+	tk.MustExec("use test")
+	tk.MustExec("create table prefetch (a int primary key, b int) partition by hash(a) partitions 4")
+	tk.MustExec("insert prefetch values (1, 1), (2, 2), (3, 3), (4, 4), (5, 5)")
+	tk.MustExec("begin optimistic")
+	tk.MustExec("delete from prefetch where a = 1")
+
+	// enable multi-statement
+	capabilities := cc.ctx.GetSessionVars().ClientCapability
+	capabilities ^= mysql.ClientMultiStatements
+	cc.ctx.SetClientCapability(capabilities)
+	query := "delete from prefetch where a = 2;" +
+		"delete from prefetch where a = 3;" +
+		"delete from prefetch where a in (4,5);"
+	err := cc.handleQuery(ctx, query)
+	require.NoError(t, err)
+	txn, err := tk.Session().Txn(false)
+	require.NoError(t, err)
+	require.True(t, txn.Valid())
+	snap := txn.GetSnapshot()
+	// TODO: support it later
+	//nolint:forcetypeassert
+	require.Equal(t, 2, snap.(snapshotCache).SnapCacheHitCount())
+	tk.MustExec("commit")
+	tk.MustQuery("select * from prefetch").Check(testkit.Rows())
+}
+
 func TestTiFlashFallback(t *testing.T) {
 	store := testkit.CreateMockStore(t,
 		mockstore.WithClusterInspector(func(c testutils.Cluster) {