This is an automated cherry-pick of pingcap#53130

0xPoe · ti-chi-bot · commit cfa4fef8943b · 2024-05-15T04:49:53.000Z
Signed-off-by: ti-chi-bot &lt;ti-community-prow-bot@tidb.io&gt;
diff --git a/executor/window_test.go b/executor/window_test.go
@@ -498,3 +498,12 @@ func TestIssue29947(t *testing.T) {
 	result.Check(testkit.Rows("2", "3"))
 	tk.MustExec("commit")
 }
+
+func TestVarSampAsAWindowFunction(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec("create table t1 (c1 int)")
+	tk.MustExec("select var_samp(c1) from t1")
+	tk.MustExec("select c1, var_samp(c1) over (partition by c1) from t1")
+}
diff --git a/parser/parser.y b/parser/parser.y
@@ -7868,7 +7868,11 @@ SumExpr:
 	}
 |	builtinVarSamp '(' BuggyDefaultFalseDistinctOpt Expression ')' OptWindowingClause
 	{
-		$$ = &ast.AggregateFuncExpr{F: $1, Args: []ast.ExprNode{$4}, Distinct: $3.(bool)}
+		if $6 != nil {
+			$$ = &ast.WindowFuncExpr{Name: $1, Args: []ast.ExprNode{$4}, Distinct: $3.(bool), Spec: *($6.(*ast.WindowSpec))}
+		} else {
+			$$ = &ast.AggregateFuncExpr{F: $1, Args: []ast.ExprNode{$4}, Distinct: $3.(bool)}
+		}
 	}
 |	"JSON_ARRAYAGG" '(' Expression ')' OptWindowingClause
 	{
diff --git a/pkg/parser/parser.go b/pkg/parser/parser.go

Original file line number	Diff line number	Diff line change
`@@ -7868,7 +7868,11 @@ SumExpr:`
`7868`	`7868`	`}`
`7869`	`7869`	`\| builtinVarSamp '(' BuggyDefaultFalseDistinctOpt Expression ')' OptWindowingClause`
`7870`	`7870`	`{`
`7871`		`- $$ = &ast.AggregateFuncExpr{F: $1, Args: []ast.ExprNode{$4}, Distinct: $3.(bool)}`
	`7871`	`+ if $6 != nil {`
	`7872`	`+ $$ = &ast.WindowFuncExpr{Name: $1, Args: []ast.ExprNode{$4}, Distinct: $3.(bool), Spec: ($6.(ast.WindowSpec))}`
	`7873`	`+ } else {`
	`7874`	`+ $$ = &ast.AggregateFuncExpr{F: $1, Args: []ast.ExprNode{$4}, Distinct: $3.(bool)}`
	`7875`	`+ }`
`7872`	`7876`	`}`
`7873`	`7877`	`\| "JSON_ARRAYAGG" '(' Expression ')' OptWindowingClause`
`7874`	`7878`	`{`