This is an automated cherry-pick of pingcap#40593

Signed-off-by: ti-chi-bot <[email protected]>

planner/core/plan_test.go

@@ -24,6 +24,7 @@ import (
 	"github.com/pingcap/tidb/config"
 	"github.com/pingcap/tidb/expression"
 	"github.com/pingcap/tidb/expression/aggregation"
+	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/parser/ast"
 	"github.com/pingcap/tidb/parser/model"
 	"github.com/pingcap/tidb/parser/mysql"
@@ -885,3 +886,72 @@ func TestNullEQConditionPlan(t *testing.T) {
 			{"Point_Get_5", "root", "handle:0"},
 		})
 }
+<<<<<<< HEAD
+=======
+
+// https://github.com/pingcap/tidb/issues/38304
+// https://github.com/pingcap/tidb/issues/38654
+func TestOuterJoinOnNull(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec("CREATE TABLE t0(c0 BLOB(5), c1 BLOB(5));")
+	tk.MustExec("CREATE TABLE t1 (c0 BOOL);")
+	tk.MustExec("INSERT INTO t1 VALUES(false);")
+	tk.MustExec("INSERT INTO t0(c0, c1) VALUES ('>', true);")
+	tk.MustQuery("SELECT * FROM t0 LEFT OUTER JOIN t1 ON NULL; ").Check(testkit.Rows("> 1 <nil>"))
+	tk.MustQuery("SELECT NOT '2' =(t1.c0 AND t0.c1 IS NULL) FROM t0 LEFT OUTER JOIN t1 ON NULL; ").Check(testkit.Rows("1"))
+	tk.MustQuery("SELECT * FROM t0 LEFT JOIN t1 ON NULL WHERE NOT '2' =(t1.c0 AND t0.c1 IS NULL); ").Check(testkit.Rows("> 1 <nil>"))
+	tk.MustQuery("SELECT * FROM t0 LEFT JOIN t1 ON NULL WHERE t1.c0 or true; ").Check(testkit.Rows("> 1 <nil>"))
+	tk.MustQuery("SELECT * FROM t0 LEFT JOIN t1 ON NULL WHERE not(t1.c0 and false); ").Check(testkit.Rows("> 1 <nil>"))
+
+	tk.MustExec("CREATE TABLE t2(c0 INT);")
+	tk.MustExec("CREATE TABLE t3(c0 INT);")
+	tk.MustExec("INSERT INTO t3 VALUES (1);")
+	tk.MustQuery("SELECT ((NOT ('i'))AND(t2.c0)) IS NULL FROM  t2 RIGHT JOIN t3 ON t3.c0;").Check(testkit.Rows("1"))
+	tk.MustQuery("SELECT * FROM t2 RIGHT JOIN t3 ON t2.c0 WHERE ((NOT ('i'))AND(t2.c0)) IS NULL;").Check(testkit.Rows("<nil> 1"))
+}
+
+func TestJSONPlanInExplain(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t1, t2")
+	tk.MustExec("create table t1(id int, key(id))")
+	tk.MustExec("create table t2(id int, key(id))")
+
+	var input []string
+	var output []struct {
+		SQL      string
+		JSONPlan []*core.ExplainInfoForEncode
+	}
+	planSuiteData := core.GetJSONPlanSuiteData()
+	planSuiteData.LoadTestCases(t, &input, &output)
+
+	for i, test := range input {
+		resJSON := tk.MustQuery(test).Rows()
+		var res []*core.ExplainInfoForEncode
+		require.NoError(t, json.Unmarshal([]byte(resJSON[0][0].(string)), &res))
+		for j, expect := range output[i].JSONPlan {
+			require.Equal(t, expect.ID, res[j].ID)
+			require.Equal(t, expect.EstRows, res[j].EstRows)
+			require.Equal(t, expect.ActRows, res[j].ActRows)
+			require.Equal(t, expect.TaskType, res[j].TaskType)
+			require.Equal(t, expect.AccessObject, res[j].AccessObject)
+			require.Equal(t, expect.OperatorInfo, res[j].OperatorInfo)
+		}
+	}
+}
+
+func TestIssue40535(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	var cfg kv.InjectionConfig
+	tk := testkit.NewTestKit(t, kv.NewInjectedStore(store, &cfg))
+	tk.MustExec("use test;")
+	tk.MustExec("drop table if exists t1; drop table if exists t2;")
+	tk.MustExec("CREATE TABLE `t1`(`c1` bigint(20) NOT NULL DEFAULT '-2312745469307452950', `c2` datetime DEFAULT '5316-02-03 06:54:49', `c3` tinyblob DEFAULT NULL, PRIMARY KEY (`c1`) /*T![clustered_index] CLUSTERED */) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin;")
+	tk.MustExec("CREATE TABLE `t2`(`c1` set('kn8pu','7et','vekx6','v3','liwrh','q14','1met','nnd5i','5o0','8cz','l') DEFAULT '7et,vekx6,liwrh,q14,1met', `c2` float DEFAULT '1.683167', KEY `k1` (`c2`,`c1`), KEY `k2` (`c2`)) ENGINE=InnoDB DEFAULT CHARSET=gbk COLLATE=gbk_chinese_ci;")
+	tk.MustExec("(select /*+ agg_to_cop()*/ locate(t1.c3, t1.c3) as r0, t1.c3 as r1 from t1 where not( IsNull(t1.c1)) order by r0,r1) union all (select concat_ws(',', t2.c2, t2.c1) as r0, t2.c1 as r1 from t2 order by r0, r1) order by 1 limit 273;")
+	require.Empty(t, tk.Session().LastMessage())
+}
+>>>>>>> 2aad38831e0 (planner: when pushing `topN` down below `proj`, check whether `topN.ByItems` contains a column(with ID=0) generated by `proj` (#40593))

planner/core/rule_topn_push_down.go

@@ -136,6 +136,20 @@ func (p *LogicalProjection) pushDownTopN(topN *LogicalTopN, opt *logicalOptimize
 				topN.ByItems = append(topN.ByItems[:i], topN.ByItems[i+1:]...)
 			}
 		}
+
+		// if topN.ByItems contains a column(with ID=0) generated by projection, projection will prevent the optimizer from pushing topN down.
+		for _, by := range topN.ByItems {
+			cols := expression.ExtractColumns(by.Expr)
+			for _, col := range cols {
+				if col.ID == 0 && p.Schema().Contains(col) {
+					// check whether the column is generated by projection
+					if !p.children[0].Schema().Contains(col) {
+						p.children[0] = p.children[0].pushDownTopN(nil, opt)
+						return topN.setChild(p, opt)
+					}
+				}
+			}
+		}
 	}
 	p.children[0] = p.children[0].pushDownTopN(topN, opt)
 	return p