.

Signed-off-by: AilinKid <[email protected]>

executor/explain_test.go

@@ -569,3 +569,37 @@ func TestExplainJSON(t *testing.T) {
 		}
 	}
 }
+
+func TestIssues49377(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists employee")
+	tk.MustExec("create table employee (employee_id int, name varchar(20), dept_id int)")
+	tk.MustExec("insert into employee values (1, 'Furina', 1), (2, 'Klee', 1), (3, 'Eula', 1), (4, 'Diluc', 2), (5, 'Tartaglia', 2)")
+
+	tk.MustQuery("select 1,1,1 union all ( " +
+		"(select * from employee where dept_id = 1) " +
+		"union all  " +
+		"(select * from employee where dept_id = 1 order by employee_id) " +
+		"order by 1 limit 1 " +
+		");").Sort().Check(testkit.Rows("1 1 1", "1 Furina 1"))
+
+	tk.MustQuery("select 1,1,1 union all ( " +
+		"(select * from employee where dept_id = 1) " +
+		"union all  " +
+		"(select * from employee where dept_id = 1 order by employee_id) " +
+		"order by 1" +
+		");").Sort().Check(testkit.Rows("1 1 1", "1 Furina 1", "1 Furina 1", "2 Klee 1", "2 Klee 1", "3 Eula 1", "3 Eula 1"))
+
+	tk.MustQuery("select * from employee where dept_id = 1 " +
+		"union all " +
+		"(select * from employee where dept_id = 1 order by employee_id) " +
+		"union all" +
+		"(" +
+		"select * from employee where dept_id = 1 " +
+		"union all " +
+		"(select * from employee where dept_id = 1 order by employee_id) " +
+		"limit 1" +
+		");").Sort().Check(testkit.Rows("1 Furina 1", "1 Furina 1", "1 Furina 1", "2 Klee 1", "2 Klee 1", "3 Eula 1", "3 Eula 1"))
+}

parser/parser.go

@@ -18356,15 +18356,21 @@ yynewstate:
 			}
 			var setOprList2 []ast.Node
 			var with2 *ast.WithClause
+			var limit2 *ast.Limit
+			var orderBy2 *ast.OrderByClause
 			switch x := yyS[yypt-0].expr.(*ast.SubqueryExpr).Query.(type) {
 			case *ast.SelectStmt:
 				setOprList2 = []ast.Node{x}
 				with2 = x.With
 			case *ast.SetOprStmt:
+				// child setOprStmt's limit and order should also make sense
+				// we should separate it out from other normal SetOprSelectList.
 				setOprList2 = x.SelectList.Selects
 				with2 = x.With
+				limit2 = x.Limit
+				orderBy2 = x.OrderBy
 			}
-			nextSetOprList := &ast.SetOprSelectList{Selects: setOprList2, With: with2}
+			nextSetOprList := &ast.SetOprSelectList{Selects: setOprList2, With: with2, Limit: limit2, OrderBy: orderBy2}
 			nextSetOprList.AfterSetOperator = yyS[yypt-1].item.(*ast.SetOprType)
 			setOprList := append(setOprList1, nextSetOprList)
 			setOpr := &ast.SetOprStmt{SelectList: &ast.SetOprSelectList{Selects: setOprList}}