planner: fallback to static plan for partition table if having no global stats in dynamic prune mode

cmd/explaintest/r/generated_columns.result

@@ -151,6 +151,7 @@ PARTITION p3 VALUES LESS THAN (4),
 PARTITION p4 VALUES LESS THAN (5),
 PARTITION p5 VALUES LESS THAN (6),
 PARTITION max VALUES LESS THAN MAXVALUE);
+analyze table sgc3;
 EXPLAIN format = 'brief' SELECT * FROM sgc3 WHERE a <= 1;
 id	estRows	task	access object	operator info
 TableReader	3323.33	root	partition:p0,p1	data:Selection

cmd/explaintest/r/select.result

@@ -381,19 +381,20 @@ PartitionUnion_8	20000.00	root
 └─TableReader_12	10000.00	root		data:TableFullScan_11
   └─TableFullScan_11	10000.00	cop[tikv]	table:th, partition:p2	keep order:false, stats:pseudo
 set @@session.tidb_partition_prune_mode = 'dynamic';
+analyze table th;
 desc select * from th where a=-2;
 id	estRows	task	access object	operator info
-TableReader_7	10.00	root	partition:p2	data:Selection_6
-└─Selection_6	10.00	cop[tikv]		eq(test.th.a, -2)
-  └─TableFullScan_5	10000.00	cop[tikv]	table:th	keep order:false, stats:pseudo
+TableReader_7	1.00	root	partition:p2	data:Selection_6
+└─Selection_6	1.00	cop[tikv]		eq(test.th.a, -2)
+  └─TableFullScan_5	17.00	cop[tikv]	table:th	keep order:false
 desc select * from th;
 id	estRows	task	access object	operator info
-TableReader_5	10000.00	root	partition:all	data:TableFullScan_4
-└─TableFullScan_4	10000.00	cop[tikv]	table:th	keep order:false, stats:pseudo
+TableReader_5	17.00	root	partition:all	data:TableFullScan_4
+└─TableFullScan_4	17.00	cop[tikv]	table:th	keep order:false
 desc select * from th partition (p2,p1);
 id	estRows	task	access object	operator info
-TableReader_5	10000.00	root	partition:p1,p2	data:TableFullScan_4
-└─TableFullScan_4	10000.00	cop[tikv]	table:th	keep order:false, stats:pseudo
+TableReader_5	17.00	root	partition:p1,p2	data:TableFullScan_4
+└─TableFullScan_4	17.00	cop[tikv]	table:th	keep order:false
 set @@session.tidb_partition_prune_mode = DEFAULT;
 drop table if exists t;
 create table t(a int, b int);

cmd/explaintest/t/generated_columns.test

@@ -107,6 +107,8 @@ PARTITION p4 VALUES LESS THAN (5),
 PARTITION p5 VALUES LESS THAN (6),
 PARTITION max VALUES LESS THAN MAXVALUE);
 
+analyze table sgc3;
+
 EXPLAIN format = 'brief' SELECT * FROM sgc3 WHERE a <= 1;
 EXPLAIN format = 'brief' SELECT * FROM sgc3 WHERE a < 7;
 

cmd/explaintest/t/select.test

@@ -190,6 +190,7 @@ desc select * from th where a=-2;
 desc select * from th;
 desc select * from th partition (p2,p1);
 set @@session.tidb_partition_prune_mode = 'dynamic';
+analyze table th;
 desc select * from th where a=-2;
 desc select * from th;
 desc select * from th partition (p2,p1);

ddl/db_partition_test.go

@@ -656,6 +656,8 @@ create table log_message_1 (
 }
 
 func TestPartitionRangeColumnsCollate(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 	tk := testkit.NewTestKit(t, store)
 	tk.MustExec("create schema PartitionRangeColumnsCollate")
@@ -3569,6 +3571,9 @@ func TestPartitionListWithTimeType(t *testing.T) {
 }
 
 func TestPartitionListWithNewCollation(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
+
 	store := testkit.CreateMockStore(t)
 	tk := testkit.NewTestKit(t, store)
 	tk.MustExec("use test;")

executor/analyzetest/analyze_test.go

@@ -2833,6 +2833,8 @@ PARTITION BY RANGE ( a ) (
 }
 
 func TestAnalyzePartitionStaticToDynamic(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store, dom := testkit.CreateMockStoreAndDomain(t)
 	tk := testkit.NewTestKit(t, store)
 	originalVal := tk.MustQuery("select @@tidb_persist_analyze_options").Rows()[0][0].(string)
@@ -2901,7 +2903,7 @@ PARTITION BY RANGE ( a ) (
 	tk.MustQuery("select * from t where a > 1 and b > 1 and c > 1 and d > 1")
 	require.NoError(t, h.LoadNeededHistograms())
 	tbl := h.GetTableStats(tableInfo)
-	require.Equal(t, 0, len(tbl.Columns))
+	require.Equal(t, 4, len(tbl.Columns))
 
 	// ignore both p0's 3 buckets, persisted-partition-options' 1 bucket, just use table-level 2 buckets
 	tk.MustExec("analyze table t partition p0")

executor/builder.go

@@ -3300,7 +3300,7 @@ func (b *executorBuilder) buildTableReader(v *plannercore.PhysicalTableReader) E
 	sctx := b.ctx.GetSessionVars().StmtCtx
 	sctx.TableIDs = append(sctx.TableIDs, ts.Table.ID)
 
-	if !b.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if !b.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		return ret
 	}
 	// When isPartition is set, it means the union rewriting is done, so a partition reader is preferred.
@@ -3504,7 +3504,7 @@ func buildNoRangeIndexReader(b *executorBuilder, v *plannercore.PhysicalIndexRea
 		e.feedback = statistics.NewQueryFeedback(0, nil, 0, is.Desc)
 	} else {
 		tblID := e.physicalTableID
-		if b.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+		if b.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 			tblID = e.table.Meta().ID
 		}
 		e.feedback = statistics.NewQueryFeedback(tblID, is.Hist, int64(is.StatsCount()), is.Desc)
@@ -3547,7 +3547,7 @@ func (b *executorBuilder) buildIndexReader(v *plannercore.PhysicalIndexReader) E
 	sctx := b.ctx.GetSessionVars().StmtCtx
 	sctx.IndexNames = append(sctx.IndexNames, is.Table.Name.O+":"+is.Index.Name.O)
 
-	if !b.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if !b.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		return ret
 	}
 	// When isPartition is set, it means the union rewriting is done, so a partition reader is preferred.
@@ -3723,7 +3723,7 @@ func (b *executorBuilder) buildIndexLookUpReader(v *plannercore.PhysicalIndexLoo
 	sctx.IndexNames = append(sctx.IndexNames, is.Table.Name.O+":"+is.Index.Name.O)
 	sctx.TableIDs = append(sctx.TableIDs, ts.Table.ID)
 
-	if !b.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if !b.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		return ret
 	}
 
@@ -3860,7 +3860,7 @@ func (b *executorBuilder) buildIndexMergeReader(v *plannercore.PhysicalIndexMerg
 	sctx.TableIDs = append(sctx.TableIDs, ts.Table.ID)
 	executorCounterIndexMergeReaderExecutor.Inc()
 
-	if !b.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if !b.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		return ret
 	}
 
@@ -3978,7 +3978,7 @@ func (builder *dataReaderBuilder) buildTableReaderForIndexJoin(ctx context.Conte
 		return nil, err
 	}
 	tbInfo := e.table.Meta()
-	if tbInfo.GetPartitionInfo() == nil || !builder.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if tbInfo.GetPartitionInfo() == nil || !builder.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		if v.IsCommonHandle {
 			kvRanges, err := buildKvRangesForIndexJoin(e.ctx, getPhysicalTableID(e.table), -1, lookUpContents, indexRanges, keyOff2IdxOff, cwc, memTracker, interruptSignal)
 			if err != nil {
@@ -4226,7 +4226,7 @@ func (builder *dataReaderBuilder) buildIndexReaderForIndexJoin(ctx context.Conte
 		return nil, err
 	}
 	tbInfo := e.table.Meta()
-	if tbInfo.GetPartitionInfo() == nil || !builder.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if tbInfo.GetPartitionInfo() == nil || !builder.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		kvRanges, err := buildKvRangesForIndexJoin(e.ctx, e.physicalTableID, e.index.ID, lookUpContents, indexRanges, keyOff2IdxOff, cwc, memoryTracker, interruptSignal)
 		if err != nil {
 			return nil, err
@@ -4273,7 +4273,7 @@ func (builder *dataReaderBuilder) buildIndexLookUpReaderForIndexJoin(ctx context
 	}
 
 	tbInfo := e.table.Meta()
-	if tbInfo.GetPartitionInfo() == nil || !builder.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if tbInfo.GetPartitionInfo() == nil || !builder.ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		e.kvRanges, err = buildKvRangesForIndexJoin(e.ctx, getPhysicalTableID(e.table), e.index.ID, lookUpContents, indexRanges, keyOff2IdxOff, cwc, memTracker, interruptSignal)
 		if err != nil {
 			return nil, err
@@ -4859,7 +4859,7 @@ func getPhysicalTableID(t table.Table) int64 {
 }
 
 func getFeedbackStatsTableID(ctx sessionctx.Context, t table.Table) int64 {
-	if p, ok := t.(table.PhysicalTable); ok && !ctx.GetSessionVars().UseDynamicPartitionPrune() {
+	if p, ok := t.(table.PhysicalTable); ok && !ctx.GetSessionVars().StmtCtx.UseDynamicPartitionPrune() {
 		return p.GetPhysicalID()
 	}
 	return t.Meta().ID

executor/distsql_test.go

@@ -291,6 +291,8 @@ func TestPushLimitDownIndexLookUpReader(t *testing.T) {
 }
 
 func TestPartitionTableIndexLookUpReader(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 	tk := testkit.NewTestKit(t, store)
 

executor/executor.go

@@ -1926,6 +1926,13 @@ func ResetContextOfStmt(ctx sessionctx.Context, s ast.StmtNode) (err error) {
 	sc.OptimizerCETrace = nil
 	sc.StatsLoadStatus = make(map[model.TableItemID]string)
 	sc.IsSyncStatsFailed = false
+	// Firstly we assume that UseDynamicPruneMode can be enabled according session variable, then we will check other conditions
+	// in PlanBuilder.buildDataSource
+	if ctx.GetSessionVars().IsDynamicPartitionPruneEnabled() {
+		sc.UseDynamicPruneMode = true
+	} else {
+		sc.UseDynamicPruneMode = false
+	}
 
 	sc.SysdateIsNow = ctx.GetSessionVars().SysdateIsNow
 

executor/executor_issue_test.go

@@ -583,6 +583,8 @@ func TestFix31537(t *testing.T) {
 }
 
 func TestIssue30382(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 	tk := testkit.NewTestKit(t, store)
 	tk.MustExec("use test")

executor/index_lookup_join_test.go

@@ -21,6 +21,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/pingcap/failpoint"
 	"github.com/pingcap/tidb/testkit"
 	"github.com/stretchr/testify/require"
 )
@@ -391,6 +392,8 @@ func TestIssue24547(t *testing.T) {
 }
 
 func TestIssue27138(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)

executor/partition_table_test.go

@@ -21,6 +21,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/pingcap/failpoint"
 	"github.com/pingcap/tidb/config"
 	"github.com/pingcap/tidb/domain"
 	"github.com/pingcap/tidb/infoschema"
@@ -33,6 +34,8 @@ import (
 )
 
 func TestFourReader(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -529,6 +532,8 @@ func TestView(t *testing.T) {
 }
 
 func TestDirectReadingwithIndexJoin(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -641,6 +646,8 @@ func TestDirectReadingwithIndexJoin(t *testing.T) {
 }
 
 func TestDynamicPruningUnderIndexJoin(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -943,6 +950,8 @@ func TestGlobalStatsAndSQLBinding(t *testing.T) {
 }
 
 func TestPartitionTableWithDifferentJoin(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -1731,6 +1740,8 @@ func TestDynamicPruneModeWithExpression(t *testing.T) {
 }
 
 func TestAddDropPartitions(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -1764,6 +1775,8 @@ func TestAddDropPartitions(t *testing.T) {
 }
 
 func TestMPPQueryExplainInfo(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -1793,6 +1806,8 @@ func TestMPPQueryExplainInfo(t *testing.T) {
 }
 
 func TestPartitionPruningInTransaction(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -2026,6 +2041,8 @@ func TestSubqueries(t *testing.T) {
 }
 
 func TestSplitRegion(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -2062,6 +2079,9 @@ func TestSplitRegion(t *testing.T) {
 }
 
 func TestParallelApply(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
+
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -2569,6 +2589,8 @@ func TestDirectReadingWithAgg(t *testing.T) {
 }
 
 func TestDynamicModeByDefault(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -2764,6 +2786,8 @@ func TestIssue25309(t *testing.T) {
 }
 
 func TestGlobalIndexScan(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)
@@ -2784,6 +2808,8 @@ partition p2 values less than (10))`)
 }
 
 func TestGlobalIndexDoubleRead(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t)
 
 	tk := testkit.NewTestKit(t, store)

executor/show_stats.go

@@ -108,7 +108,7 @@ func (e *ShowExec) fetchShowStatsMeta() error {
 	for _, db := range dbs {
 		for _, tbl := range db.Tables {
 			pi := tbl.GetPartitionInfo()
-			if pi == nil || e.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+			if pi == nil || e.ctx.GetSessionVars().IsDynamicPartitionPruneEnabled() {
 				partitionName := ""
 				if pi != nil {
 					partitionName = "global"
@@ -150,7 +150,7 @@ func (e *ShowExec) fetchShowStatsHistogram() error {
 	for _, db := range dbs {
 		for _, tbl := range db.Tables {
 			pi := tbl.GetPartitionInfo()
-			if pi == nil || e.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+			if pi == nil || e.ctx.GetSessionVars().IsDynamicPartitionPruneEnabled() {
 				partitionName := ""
 				if pi != nil {
 					partitionName = "global"
@@ -224,7 +224,7 @@ func (e *ShowExec) fetchShowStatsBuckets() error {
 	for _, db := range dbs {
 		for _, tbl := range db.Tables {
 			pi := tbl.GetPartitionInfo()
-			if pi == nil || e.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+			if pi == nil || e.ctx.GetSessionVars().IsDynamicPartitionPruneEnabled() {
 				partitionName := ""
 				if pi != nil {
 					partitionName = "global"
@@ -283,7 +283,7 @@ func (e *ShowExec) fetchShowStatsTopN() error {
 	for _, db := range dbs {
 		for _, tbl := range db.Tables {
 			pi := tbl.GetPartitionInfo()
-			if pi == nil || e.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+			if pi == nil || e.ctx.GetSessionVars().IsDynamicPartitionPruneEnabled() {
 				partitionName := ""
 				if pi != nil {
 					partitionName = "global"
@@ -415,7 +415,7 @@ func (e *ShowExec) fetchShowStatsHealthy() {
 	for _, db := range dbs {
 		for _, tbl := range db.Tables {
 			pi := tbl.GetPartitionInfo()
-			if pi == nil || e.ctx.GetSessionVars().UseDynamicPartitionPrune() {
+			if pi == nil || e.ctx.GetSessionVars().IsDynamicPartitionPruneEnabled() {
 				partitionName := ""
 				if pi != nil {
 					partitionName = "global"

executor/tiflashtest/tiflash_test.go

@@ -457,6 +457,8 @@ func TestTiFlashPartitionTableReader(t *testing.T) {
 }
 
 func TestPartitionTable(t *testing.T) {
+	failpoint.Enable("github.com/pingcap/tidb/planner/core/forceDynamicPrune", `return(true)`)
+	defer failpoint.Disable("github.com/pingcap/tidb/planner/core/forceDynamicPrune")
 	store := testkit.CreateMockStore(t, withMockTiFlash(2))
 	tk := testkit.NewTestKit(t, store)
 	tk.MustExec("use test")