planner: set EnableOuterJoinReorder to false by default (#37264)

ref #37238
pingcap · Aug 22, 2022 · 21847fe · 21847fe
1 parent ffc5e17
commit 21847fe
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Showing 10 changed files with 19 additions and 3 deletions.
diff --git a/cmd/explaintest/r/clustered_index.result b/cmd/explaintest/r/clustered_index.result
@@ -1,3 +1,4 @@
+set @@tidb_enable_outer_join_reorder=true;
 drop database if exists with_cluster_index;
 create database with_cluster_index;
 drop database if exists wout_cluster_index;
@@ -127,3 +128,4 @@ StreamAgg_17	1.00	root		funcs:count(Column#9)->Column#7
 └─IndexReader_18	1.00	root		index:StreamAgg_9
   └─StreamAgg_9	1.00	cop[tikv]		funcs:count(1)->Column#9
     └─IndexRangeScan_16	109.70	cop[tikv]	table:tbl_0, index:idx_3(col_0)	range:[803163,+inf], keep order:false
+set @@tidb_enable_outer_join_reorder=false;
diff --git a/cmd/explaintest/r/select.result b/cmd/explaintest/r/select.result
@@ -1,3 +1,4 @@
+set @@tidb_enable_outer_join_reorder=true;
 DROP TABLE IF EXISTS t;
 CREATE TABLE t (
 c1 int,
@@ -654,3 +655,4 @@ create table t3(a char(10), primary key (a));
 insert into t3 values ('a');
 select * from t3 where a > 0x80;
 Error 1105: Cannot convert string '\x80' from binary to utf8mb4
+set @@tidb_enable_outer_join_reorder=false;
diff --git a/cmd/explaintest/t/clustered_index.test b/cmd/explaintest/t/clustered_index.test
@@ -1,3 +1,4 @@
+set @@tidb_enable_outer_join_reorder=true;
 drop database if exists with_cluster_index;
 create database with_cluster_index;
 drop database if exists wout_cluster_index;
@@ -53,3 +54,4 @@ explain select count(*) from wout_cluster_index.tbl_0 where col_0 <= 0 ;
 
 explain select count(*) from with_cluster_index.tbl_0 where col_0 >= 803163  ;
 explain select count(*) from wout_cluster_index.tbl_0 where col_0 >= 803163  ;
+set @@tidb_enable_outer_join_reorder=false;
diff --git a/cmd/explaintest/t/select.test b/cmd/explaintest/t/select.test
@@ -1,3 +1,4 @@
+set @@tidb_enable_outer_join_reorder=true;
 DROP TABLE IF EXISTS t;
 
 CREATE TABLE t (
@@ -279,3 +280,4 @@ create table t3(a char(10), primary key (a));
 insert into t3 values ('a');
 --error 1105
 select * from t3 where a > 0x80;
+set @@tidb_enable_outer_join_reorder=false;
diff --git a/planner/core/rule_join_reorder_test.go b/planner/core/rule_join_reorder_test.go
@@ -228,6 +228,7 @@ func TestJoinOrderHint4StaticPartitionTable(t *testing.T) {
 	tk.MustExec(`create table t6(a int, b int) partition by hash(b) partitions 3`)
 
 	tk.MustExec(`set @@tidb_partition_prune_mode="static"`)
+	tk.MustExec("set @@tidb_enable_outer_join_reorder=true")
 	runJoinReorderTestData(t, tk, "TestJoinOrderHint4StaticPartitionTable")
 }
 
@@ -246,6 +247,7 @@ func TestJoinOrderHint4DynamicPartitionTable(t *testing.T) {
 	tk.MustExec(`create table t6(a int, b int) partition by hash(b) partitions 3`)
 
 	tk.MustExec(`set @@tidb_partition_prune_mode="dynamic"`)
+	tk.MustExec("set @@tidb_enable_outer_join_reorder=true")
 	runJoinReorderTestData(t, tk, "TestJoinOrderHint4DynamicPartitionTable")
 }
 
@@ -264,6 +266,7 @@ func TestJoinOrderHint4DifferentJoinType(t *testing.T) {
 	tk.MustExec("create table t6(a int, b int, key(a));")
 	tk.MustExec("create table t7(a int, b int, key(a));")
 	tk.MustExec("create table t8(a int, b int, key(a));")
+	tk.MustExec("set @@tidb_enable_outer_join_reorder=true")
 
 	runJoinReorderTestData(t, tk, "TestJoinOrderHint4DifferentJoinType")
 }
@@ -280,6 +283,7 @@ func TestJoinOrderHint4TiFlash(t *testing.T) {
 	tk.MustExec("create table t4(a int, b int, key(a));")
 	tk.MustExec("create table t5(a int, b int, key(a));")
 	tk.MustExec("create table t6(a int, b int, key(a));")
+	tk.MustExec("set @@tidb_enable_outer_join_reorder=true")
 
 	// Create virtual tiflash replica info.
 	dom := domain.GetDomain(tk.Session())
@@ -336,6 +340,7 @@ func TestLeadingJoinHint4OuterJoin(t *testing.T) {
 	tk.MustExec("create table t6(a int, b int, key(a));")
 	tk.MustExec("create table t7(a int, b int, key(a));")
 	tk.MustExec("create table t8(a int, b int, key(a));")
+	tk.MustExec("set @@tidb_enable_outer_join_reorder=true")
 	runJoinReorderTestData(t, tk, "TestLeadingJoinHint4OuterJoin")
 }
 

diff --git a/planner/core/rule_result_reorder_test.go b/planner/core/rule_result_reorder_test.go
@@ -147,6 +147,7 @@ func TestOrderedResultModeOnJoin(t *testing.T) {
 	tk.MustExec("drop table if exists t2")
 	tk.MustExec("create table t1 (a int primary key, b int, c int, d int, key(b))")
 	tk.MustExec("create table t2 (a int primary key, b int, c int, d int, key(b))")
+	tk.MustExec("set @@tidb_enable_outer_join_reorder=true")
 	runTestData(t, tk, "TestOrderedResultModeOnJoin")
 }
 

diff --git a/sessionctx/variable/sysvar.go b/sessionctx/variable/sysvar.go
@@ -219,7 +219,7 @@ var defaultSysVars = []*SysVar{
 		s.OptimizerSelectivityLevel = tidbOptPositiveInt32(val, DefTiDBOptimizerSelectivityLevel)
 		return nil
 	}},
-	{Scope: ScopeGlobal | ScopeSession, Name: TiDBOptimizerEnableOuterJoinReorder, Value: BoolToOnOff(DefTiDBEnableOuterJoinReorder), skipInit: true, Type: TypeBool, SetSession: func(s *SessionVars, val string) error {
+	{Scope: ScopeGlobal | ScopeSession, Name: TiDBOptimizerEnableOuterJoinReorder, Value: BoolToOnOff(DefTiDBEnableOuterJoinReorder), Type: TypeBool, SetSession: func(s *SessionVars, val string) error {
 		s.EnableOuterJoinReorder = TiDBOptOn(val)
 		return nil
 	}},

diff --git a/sessionctx/variable/sysvar_test.go b/sessionctx/variable/sysvar_test.go
@@ -719,7 +719,6 @@ func TestSkipInitIsUsed(t *testing.T) {
 				TiDBSnapshot,
 				TiDBEnableChunkRPC,
 				TxnIsolationOneShot,
-				TiDBOptimizerEnableOuterJoinReorder,
 				TiDBDDLReorgPriority,
 				TiDBSlowQueryFile,
 				TiDBWaitSplitRegionFinish,

diff --git a/sessionctx/variable/tidb_vars.go b/sessionctx/variable/tidb_vars.go
@@ -881,7 +881,7 @@ const (
 	DefBroadcastJoinThresholdCount                 = 10 * 1024
 	DefTiDBOptimizerSelectivityLevel               = 0
 	DefTiDBOptimizerEnableNewOFGB                  = false
-	DefTiDBEnableOuterJoinReorder                  = true
+	DefTiDBEnableOuterJoinReorder                  = false
 	DefTiDBAllowBatchCop                           = 1
 	DefTiDBAllowMPPExecution                       = true
 	DefTiDBHashExchangeWithNewCollation            = true

diff --git a/sessionctx/variable/varsutil_test.go b/sessionctx/variable/varsutil_test.go
@@ -241,6 +241,9 @@ func TestVarsutil(t *testing.T) {
 	err = v.SetSystemVar(TiDBOptimizerEnableOuterJoinReorder, "OFF")
 	require.NoError(t, err)
 	require.Equal(t, false, v.EnableOuterJoinReorder)
+	err = v.SetSystemVar(TiDBOptimizerEnableOuterJoinReorder, "ON")
+	require.NoError(t, err)
+	require.Equal(t, true, v.EnableOuterJoinReorder)
 
 	require.Equal(t, DefTiDBOptimizerEnableNewOFGB, v.OptimizerEnableNewOnlyFullGroupByCheck)
 	err = v.SetSystemVar(TiDBOptimizerEnableNewOnlyFullGroupByCheck, "off")