planner: should clone column in injectProjBelowSort (pingcap#10452)

Author: winoros

executor/executor_test.go

@@ -3782,6 +3782,19 @@ func (s *testSuite) TestSplitIndexRegion(c *C) {
 	c.Assert(terr.Code(), Equals, terror.ErrCode(mysql.WarnDataTruncated))
 }
 
+func (s *testSuite) TestIssue10435(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("create table t1(i int, j int, k int)")
+	tk.MustExec("insert into t1 VALUES (1,1,1),(2,2,2),(3,3,3),(4,4,4)")
+	tk.MustExec("INSERT INTO t1 SELECT 10*i,j,5*j FROM t1 UNION SELECT 20*i,j,5*j FROM t1 UNION SELECT 30*i,j,5*j FROM t1")
+
+	tk.MustExec("set @@session.tidb_enable_window_function=1")
+	tk.MustQuery("SELECT SUM(i) OVER W FROM t1 WINDOW w AS (PARTITION BY j ORDER BY i) ORDER BY 1+SUM(i) OVER w").Check(
+		testkit.Rows("1", "2", "3", "4", "11", "22", "31", "33", "44", "61", "62", "93", "122", "124", "183", "244"),
+	)
+}
+
 func (s *testSuite) TestUnsignedFeedback(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 	oriProbability := statistics.FeedbackProbability.Load()

planner/core/rule_inject_extra_projection.go

@@ -157,7 +157,7 @@ func injectProjBelowSort(p PhysicalPlan, orderByItems []*ByItems) PhysicalPlan {
 
 	topProjExprs := make([]expression.Expression, 0, p.Schema().Len())
 	for i := range p.Schema().Columns {
-		col := p.Schema().Columns[i]
+		col := p.Schema().Columns[i].Clone().(*expression.Column)
 		col.Index = i
 		topProjExprs = append(topProjExprs, col)
 	}
@@ -172,9 +172,10 @@ func injectProjBelowSort(p PhysicalPlan, orderByItems []*ByItems) PhysicalPlan {
 	bottomProjSchemaCols := make([]*expression.Column, 0, len(childPlan.Schema().Columns)+numOrderByItems)
 	bottomProjExprs := make([]expression.Expression, 0, len(childPlan.Schema().Columns)+numOrderByItems)
 	for i, col := range childPlan.Schema().Columns {
-		col.Index = i
-		bottomProjSchemaCols = append(bottomProjSchemaCols, col)
-		bottomProjExprs = append(bottomProjExprs, col)
+		newCol := col.Clone().(*expression.Column)
+		newCol.Index = i
+		bottomProjSchemaCols = append(bottomProjSchemaCols, newCol)
+		bottomProjExprs = append(bottomProjExprs, newCol)
 	}
 
 	for _, item := range orderByItems {