cherry pick pingcap#27798 to release-5.0

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

planner/core/integration_test.go

@@ -3724,3 +3724,74 @@ func (s *testIntegrationSuite) TestGroupBySetVar(c *C) {
 		res.Check(testkit.Rows(output[i].Plan...))
 	}
 }
+<<<<<<< HEAD
+=======
+
+func (s *testIntegrationSerialSuite) TestPushDownGroupConcatToTiFlash(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists ts")
+	tk.MustExec("create table ts (col_0 char(64), col_1 varchar(64) not null, col_2 varchar(1), id int primary key);")
+
+	// Create virtual tiflash replica info.
+	dom := domain.GetDomain(tk.Se)
+	is := dom.InfoSchema()
+	db, exists := is.SchemaByName(model.NewCIStr("test"))
+	c.Assert(exists, IsTrue)
+	for _, tblInfo := range db.Tables {
+		if tblInfo.Name.L == "ts" {
+			tblInfo.TiFlashReplica = &model.TiFlashReplicaInfo{
+				Count:     1,
+				Available: true,
+			}
+		}
+	}
+
+	tk.MustExec("set @@tidb_isolation_read_engines='tiflash,tidb'; set @@tidb_allow_mpp=1; set @@tidb_enforce_mpp=1;")
+
+	var input []string
+	var output []struct {
+		SQL  string
+		Plan []string
+	}
+	s.testData.GetTestCases(c, &input, &output)
+	for i, tt := range input {
+		s.testData.OnRecord(func() {
+			output[i].SQL = tt
+			output[i].Plan = s.testData.ConvertRowsToStrings(tk.MustQuery(tt).Rows())
+		})
+		res := tk.MustQuery(tt)
+		res.Check(testkit.Rows(output[i].Plan...))
+	}
+}
+
+func (s *testIntegrationSuite) TestIssue27797(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t27797")
+	tk.MustExec("create table t27797(a int, b int, c int, d int) " +
+		"partition by range columns(d) (" +
+		"partition p0 values less than (20)," +
+		"partition p1 values less than(40)," +
+		"partition p2 values less than(60));")
+	tk.MustExec("insert into t27797 values(1,1,1,1), (2,2,2,2), (22,22,22,22), (44,44,44,44);")
+	tk.MustExec("set sql_mode='';")
+	result := tk.MustQuery("select count(*) from (select a, b from t27797 where d > 1 and d < 60 and b > 0 group by b, c) tt;")
+	result.Check(testkit.Rows("3"))
+
+	tk.MustExec("drop table if exists IDT_HP24172")
+	tk.MustExec("CREATE TABLE `IDT_HP24172` ( " +
+		"`COL1` mediumint(16) DEFAULT NULL, " +
+		"`COL2` varchar(20) DEFAULT NULL, " +
+		"`COL4` datetime DEFAULT NULL, " +
+		"`COL3` bigint(20) DEFAULT NULL, " +
+		"`COL5` float DEFAULT NULL, " +
+		"KEY `UM_COL` (`COL1`,`COL3`) " +
+		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin " +
+		"PARTITION BY HASH( `COL1`+`COL3` ) " +
+		"PARTITIONS 8;")
+	tk.MustExec("insert into IDT_HP24172(col1) values(8388607);")
+	result = tk.MustQuery("select col2 from IDT_HP24172 where col1 = 8388607 and col1 in (select col1 from IDT_HP24172);")
+	result.Check(testkit.Rows("<nil>"))
+}
+>>>>>>> 68e32bb44... planner: fix wrong plan caused by shallow copy schema columns (#27798)

planner/core/rule_aggregation_push_down.go

@@ -380,7 +380,7 @@ func (a *aggregationPushDownSolver) tryAggPushDownForUnion(union *LogicalUnionAl
 		}
 		newChildren = append(newChildren, newChild)
 	}
-	union.SetSchema(expression.NewSchema(newChildren[0].Schema().Columns...))
+	union.SetSchema(expression.NewSchema(newChildren[0].Schema().Clone().Columns...))
 	union.SetChildren(newChildren...)
 	return nil
 }