parser: skip restoring schema name of CTE table columns (#33991)

executor/cte_test.go

@@ -440,3 +440,23 @@ func TestCTEExecError(t *testing.T) {
 		require.True(t, terror.ErrorEqual(err, types.ErrOverflow))
 	}
 }
+
+// https://github.com/pingcap/tidb/issues/33965.
+func TestCTEsInView(t *testing.T) {
+	store, clean := testkit.CreateMockStore(t)
+	defer clean()
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test;")
+
+	tk.MustExec("create database if not exists test1;")
+	tk.MustExec("create table test.t (a int);")
+	tk.MustExec("create table test1.t (a int);")
+	tk.MustExec("insert into test.t values (1);")
+	tk.MustExec("insert into test1.t values (2);")
+
+	tk.MustExec("use test;")
+	tk.MustExec("create definer='root'@'localhost' view test.v as with tt as (select * from t) select * from tt;")
+	tk.MustQuery("select * from test.v;").Check(testkit.Rows("1"))
+	tk.MustExec("use test1;")
+	tk.MustQuery("select * from test.v;").Check(testkit.Rows("1"))
+}

parser/ast/dml.go

@@ -14,8 +14,6 @@
 package ast
 
 import (
-	"strings"
-
 	"github.com/pingcap/errors"
 	"github.com/pingcap/tidb/parser/auth"
 	"github.com/pingcap/tidb/parser/format"
@@ -286,14 +284,7 @@ func (n *TableName) restoreName(ctx *format.RestoreCtx) {
 		ctx.WritePlain(".")
 	} else if ctx.DefaultDB != "" {
 		// Try CTE, for a CTE table name, we shouldn't write the database name.
-		ok := false
-		for _, name := range ctx.CTENames {
-			if strings.EqualFold(name, n.Name.String()) {
-				ok = true
-				break
-			}
-		}
-		if !ok {
+		if !ctx.IsCTETableName(n.Name.L) {
 			ctx.WriteName(ctx.DefaultDB)
 			ctx.WritePlain(".")
 		}
@@ -1119,7 +1110,7 @@ func (n *WithClause) Restore(ctx *format.RestoreCtx) error {
 		if n.IsRecursive {
 			// If the CTE is recursive, we should make it visible for the CTE's query.
 			// Otherwise, we should put it to stack after building the CTE's query.
-			ctx.CTENames = append(ctx.CTENames, cte.Name.L)
+			ctx.RecordCTEName(cte.Name.L)
 		}
 		if len(cte.ColNameList) > 0 {
 			ctx.WritePlain(" (")
@@ -1137,7 +1128,7 @@ func (n *WithClause) Restore(ctx *format.RestoreCtx) error {
 			return err
 		}
 		if !n.IsRecursive {
-			ctx.CTENames = append(ctx.CTENames, cte.Name.L)
+			ctx.RecordCTEName(cte.Name.L)
 		}
 	}
 	ctx.WritePlain(" ")
@@ -1163,10 +1154,7 @@ func (n *WithClause) Accept(v Visitor) (Node, bool) {
 // Restore implements Node interface.
 func (n *SelectStmt) Restore(ctx *format.RestoreCtx) error {
 	if n.WithBeforeBraces {
-		l := len(ctx.CTENames)
-		defer func() {
-			ctx.CTENames = ctx.CTENames[:l]
-		}()
+		defer ctx.RestoreCTEFunc()()
 		err := n.With.Restore(ctx)
 		if err != nil {
 			return err
@@ -1514,10 +1502,7 @@ type SetOprSelectList struct {
 // Restore implements Node interface.
 func (n *SetOprSelectList) Restore(ctx *format.RestoreCtx) error {
 	if n.With != nil {
-		l := len(ctx.CTENames)
-		defer func() {
-			ctx.CTENames = ctx.CTENames[:l]
-		}()
+		defer ctx.RestoreCTEFunc()()
 		if err := n.With.Restore(ctx); err != nil {
 			return errors.Annotate(err, "An error occurred while restore SetOprSelectList.With")
 		}
@@ -1618,10 +1603,7 @@ func (*SetOprStmt) resultSet() {}
 // Restore implements Node interface.
 func (n *SetOprStmt) Restore(ctx *format.RestoreCtx) error {
 	if n.With != nil {
-		l := len(ctx.CTENames)
-		defer func() {
-			ctx.CTENames = ctx.CTENames[:l]
-		}()
+		defer ctx.RestoreCTEFunc()()
 		if err := n.With.Restore(ctx); err != nil {
 			return errors.Annotate(err, "An error occurred while restore UnionStmt.With")
 		}
@@ -2203,10 +2185,7 @@ type DeleteStmt struct {
 // Restore implements Node interface.
 func (n *DeleteStmt) Restore(ctx *format.RestoreCtx) error {
 	if n.With != nil {
-		l := len(ctx.CTENames)
-		defer func() {
-			ctx.CTENames = ctx.CTENames[:l]
-		}()
+		defer ctx.RestoreCTEFunc()()
 		err := n.With.Restore(ctx)
 		if err != nil {
 			return err
@@ -2367,10 +2346,7 @@ type UpdateStmt struct {
 // Restore implements Node interface.
 func (n *UpdateStmt) Restore(ctx *format.RestoreCtx) error {
 	if n.With != nil {
-		l := len(ctx.CTENames)
-		defer func() {
-			ctx.CTENames = ctx.CTENames[:l]
-		}()
+		defer ctx.RestoreCTEFunc()()
 		err := n.With.Restore(ctx)
 		if err != nil {
 			return err

parser/ast/expressions.go

@@ -512,7 +512,7 @@ type ColumnName struct {
 
 // Restore implements Node interface.
 func (n *ColumnName) Restore(ctx *format.RestoreCtx) error {
-	if n.Schema.O != "" {
+	if n.Schema.O != "" && !ctx.IsCTETableName(n.Table.L) {
 		ctx.WriteName(n.Schema.O)
 		ctx.WritePlain(".")
 	}

parser/format/format.go

@@ -305,12 +305,12 @@ type RestoreCtx struct {
 	Flags     RestoreFlags
 	In        io.Writer
 	DefaultDB string
-	CTENames  []string
+	CTERestorer
 }
 
 // NewRestoreCtx returns a new `RestoreCtx`.
 func NewRestoreCtx(flags RestoreFlags, in io.Writer) *RestoreCtx {
-	return &RestoreCtx{flags, in, "", make([]string, 0)}
+	return &RestoreCtx{Flags: flags, In: in, DefaultDB: ""}
 }
 
 // WriteKeyWord writes the `keyWord` into writer.
@@ -387,3 +387,33 @@ func (ctx *RestoreCtx) WritePlain(plainText string) {
 func (ctx *RestoreCtx) WritePlainf(format string, a ...interface{}) {
 	fmt.Fprintf(ctx.In, format, a...)
 }
+
+// CTERestorer is used by WithClause related nodes restore.
+type CTERestorer struct {
+	CTENames []string
+}
+
+// IsCTETableName returns true if the given tableName comes from CTE.
+func (c *CTERestorer) IsCTETableName(nameL string) bool {
+	for _, n := range c.CTENames {
+		if n == nameL {
+			return true
+		}
+	}
+	return false
+}
+
+func (c *CTERestorer) RecordCTEName(nameL string) {
+	c.CTENames = append(c.CTENames, nameL)
+}
+
+func (c *CTERestorer) RestoreCTEFunc() func() {
+	l := len(c.CTENames)
+	return func() {
+		if l == 0 {
+			c.CTENames = nil
+		} else {
+			c.CTENames = c.CTENames[:l]
+		}
+	}
+}