resolved conflict and add more test cases

cmd/explaintest/r/explain_easy.result

@@ -79,9 +79,9 @@ TopN_7	1.00	root	test.t2.c2:asc, offset:0, count:1
     └─TableScan_13	10000.00	cop[tikv]	table:t2, range:[-inf,+inf], keep order:false, stats:pseudo
 explain select * from t1 where c1 > 1 and c2 = 1 and c3 < 1;
 id	count	task	operator info
-IndexLookUp_11	1.11	root	
+IndexLookUp_11	11.08	root	
 ├─IndexScan_8	33.33	cop[tikv]	table:t1, index:c2, range:(1 1,1 +inf], keep order:false, stats:pseudo
-└─Selection_10	1.11	cop[tikv]	lt(test.t1.c3, 1)
+└─Selection_10	11.08	cop[tikv]	lt(test.t1.c3, 1)
   └─TableScan_9	33.33	cop[tikv]	table:t1, keep order:false, stats:pseudo
 explain select * from t1 where c1 = 1 and c2 > 1;
 id	count	task	operator info

ddl/db_integration_test.go

@@ -1043,6 +1043,7 @@ func (s *testIntegrationSuite5) TestBackwardCompatibility(c *C) {
 	err = txn.Commit(context.Background())
 	c.Assert(err, IsNil)
 	ticker := time.NewTicker(s.lease)
+	defer ticker.Stop()
 	for range ticker.C {
 		historyJob, err := s.getHistoryDDLJob(job.ID)
 		c.Assert(err, IsNil)

domain/schema_validator_test.go

@@ -128,6 +128,7 @@ func serverFunc(lease time.Duration, requireLease chan leaseGrantItem, oracleCh
 	var version int64
 	leaseTS := uint64(time.Now().UnixNano())
 	ticker := time.NewTicker(lease)
+	defer ticker.Stop()
 	for {
 		select {
 		case now := <-ticker.C:

executor/adapter.go

@@ -254,7 +254,7 @@ func (a *ExecStmt) IsReadOnly(vars *variable.SessionVars) bool {
 // RebuildPlan rebuilds current execute statement plan.
 // It returns the current information schema version that 'a' is using.
 func (a *ExecStmt) RebuildPlan(ctx context.Context) (int64, error) {
-	is := GetInfoSchema(a.Ctx)
+	is := infoschema.GetInfoSchema(a.Ctx)
 	a.InfoSchema = is
 	if err := plannercore.Preprocess(a.Ctx, a.StmtNode, is, plannercore.InTxnRetry); err != nil {
 		return 0, err

executor/analyze.go

@@ -34,6 +34,7 @@ import (
 	"github.com/pingcap/parser/mysql"
 	"github.com/pingcap/tidb/distsql"
 	"github.com/pingcap/tidb/domain"
+	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/metrics"
 	"github.com/pingcap/tidb/sessionctx"
@@ -125,7 +126,7 @@ func (e *AnalyzeExec) Next(ctx context.Context, req *chunk.Chunk) error {
 	if err != nil {
 		return err
 	}
-	return statsHandle.Update(GetInfoSchema(e.ctx))
+	return statsHandle.Update(infoschema.GetInfoSchema(e.ctx))
 }
 
 func getBuildStatsConcurrency(ctx sessionctx.Context) (int, error) {

executor/analyze_test.go

@@ -27,6 +27,7 @@ import (
 	"github.com/pingcap/parser/mysql"
 	"github.com/pingcap/tidb/domain"
 	"github.com/pingcap/tidb/executor"
+	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/session"
 	"github.com/pingcap/tidb/sessionctx"
@@ -62,7 +63,7 @@ PARTITION BY RANGE ( a ) (
 	}
 	tk.MustExec("analyze table t")
 
-	is := executor.GetInfoSchema(tk.Se.(sessionctx.Context))
+	is := infoschema.GetInfoSchema(tk.Se.(sessionctx.Context))
 	table, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
 	c.Assert(err, IsNil)
 	pi := table.Meta().GetPartitionInfo()
@@ -89,7 +90,7 @@ PARTITION BY RANGE ( a ) (
 		tk.MustExec(fmt.Sprintf(`insert into t values (%d, %d, "hello")`, i, i))
 	}
 	tk.MustExec("alter table t analyze partition p0")
-	is = executor.GetInfoSchema(tk.Se.(sessionctx.Context))
+	is = infoschema.GetInfoSchema(tk.Se.(sessionctx.Context))
 	table, err = is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
 	c.Assert(err, IsNil)
 	pi = table.Meta().GetPartitionInfo()
@@ -139,7 +140,7 @@ func (s *testSuite1) TestAnalyzeParameters(c *C) {
 
 	tk.MustExec("set @@tidb_enable_fast_analyze = 1")
 	tk.MustExec("analyze table t with 30 samples")
-	is := executor.GetInfoSchema(tk.Se.(sessionctx.Context))
+	is := infoschema.GetInfoSchema(tk.Se.(sessionctx.Context))
 	table, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
 	c.Assert(err, IsNil)
 	tableInfo := table.Meta()
@@ -170,7 +171,7 @@ func (s *testSuite1) TestAnalyzeTooLongColumns(c *C) {
 	tk.MustExec(fmt.Sprintf("insert into t values ('%s')", value))
 
 	tk.MustExec("analyze table t")
-	is := executor.GetInfoSchema(tk.Se.(sessionctx.Context))
+	is := infoschema.GetInfoSchema(tk.Se.(sessionctx.Context))
 	table, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
 	c.Assert(err, IsNil)
 	tableInfo := table.Meta()
@@ -311,7 +312,7 @@ func (s *testFastAnalyze) TestFastAnalyze(c *C) {
 	}
 	tk.MustExec("analyze table t with 5 buckets, 6 samples")
 
-	is := executor.GetInfoSchema(tk.Se.(sessionctx.Context))
+	is := infoschema.GetInfoSchema(tk.Se.(sessionctx.Context))
 	table, err := is.TableByName(model.NewCIStr("test"), model.NewCIStr("t"))
 	c.Assert(err, IsNil)
 	tableInfo := table.Meta()

executor/bind.go

@@ -20,6 +20,7 @@ import (
 	"github.com/pingcap/parser/ast"
 	"github.com/pingcap/tidb/bindinfo"
 	"github.com/pingcap/tidb/domain"
+	"github.com/pingcap/tidb/infoschema"
 	plannercore "github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/util/chunk"
 )
@@ -72,9 +73,9 @@ func (e *SQLBindExec) dropSQLBind() error {
 	}
 	if !e.isGlobal {
 		handle := e.ctx.Value(bindinfo.SessionBindInfoKeyType).(*bindinfo.SessionHandle)
-		return handle.DropBindRecord(e.ctx, GetInfoSchema(e.ctx), record)
+		return handle.DropBindRecord(e.ctx, infoschema.GetInfoSchema(e.ctx), record)
 	}
-	return domain.GetDomain(e.ctx).BindHandle().DropBindRecord(e.ctx, GetInfoSchema(e.ctx), record)
+	return domain.GetDomain(e.ctx).BindHandle().DropBindRecord(e.ctx, infoschema.GetInfoSchema(e.ctx), record)
 }
 
 func (e *SQLBindExec) createSQLBind() error {
@@ -91,9 +92,9 @@ func (e *SQLBindExec) createSQLBind() error {
 	}
 	if !e.isGlobal {
 		handle := e.ctx.Value(bindinfo.SessionBindInfoKeyType).(*bindinfo.SessionHandle)
-		return handle.AddBindRecord(e.ctx, GetInfoSchema(e.ctx), record)
+		return handle.AddBindRecord(e.ctx, infoschema.GetInfoSchema(e.ctx), record)
 	}
-	return domain.GetDomain(e.ctx).BindHandle().AddBindRecord(e.ctx, GetInfoSchema(e.ctx), record)
+	return domain.GetDomain(e.ctx).BindHandle().AddBindRecord(e.ctx, infoschema.GetInfoSchema(e.ctx), record)
 }
 
 func (e *SQLBindExec) flushBindings() error {

executor/compiler.go

@@ -25,8 +25,6 @@ import (
 	"github.com/pingcap/tidb/planner"
 	plannercore "github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/sessionctx"
-	"github.com/pingcap/tidb/util/logutil"
-	"go.uber.org/zap"
 )
 
 var (
@@ -55,7 +53,7 @@ func (c *Compiler) Compile(ctx context.Context, stmtNode ast.StmtNode) (*ExecStm
 		ctx = opentracing.ContextWithSpan(ctx, span1)
 	}
 
-	infoSchema := GetInfoSchema(c.Ctx)
+	infoSchema := infoschema.GetInfoSchema(c.Ctx)
 	if err := plannercore.Preprocess(c.Ctx, stmtNode, infoSchema); err != nil {
 		return nil, err
 	}
@@ -347,17 +345,3 @@ func GetStmtLabel(stmtNode ast.StmtNode) string {
 	}
 	return "other"
 }
-
-// GetInfoSchema gets TxnCtx InfoSchema if snapshot schema is not set,
-// Otherwise, snapshot schema is returned.
-func GetInfoSchema(ctx sessionctx.Context) infoschema.InfoSchema {
-	sessVar := ctx.GetSessionVars()
-	var is infoschema.InfoSchema
-	if snap := sessVar.SnapshotInfoschema; snap != nil {
-		is = snap.(infoschema.InfoSchema)
-		logutil.BgLogger().Info("use snapshot schema", zap.Uint64("conn", sessVar.ConnectionID), zap.Int64("schemaVersion", is.SchemaMetaVersion()))
-	} else {
-		is = sessVar.TxnCtx.InfoSchema.(infoschema.InfoSchema)
-	}
-	return is
-}

executor/executor.go

@@ -1618,14 +1618,8 @@ func ResetContextOfStmt(ctx sessionctx.Context, s ast.StmtNode) (err error) {
 		sc.PrevAffectedRows = -1
 	}
 	errCount, warnCount := vars.StmtCtx.NumErrorWarnings()
-	err = vars.SetSystemVar("warning_count", warnCount)
-	if err != nil {
-		return err
-	}
-	err = vars.SetSystemVar("error_count", errCount)
-	if err != nil {
-		return err
-	}
+	vars.SysErrorCount = errCount
+	vars.SysWarningCount = warnCount
 	vars.StmtCtx = sc
 	for _, warn := range hintWarns {
 		vars.StmtCtx.AppendWarning(warn)

executor/executor_test.go

@@ -2089,7 +2089,7 @@ func (s *testSuiteP2) TestIsPointGet(c *C) {
 		"select * from help_topic where help_topic_id=1":    true,
 		"select * from help_topic where help_category_id=1": false,
 	}
-	infoSchema := executor.GetInfoSchema(ctx)
+	infoSchema := infoschema.GetInfoSchema(ctx)
 
 	for sqlStr, result := range tests {
 		stmtNode, err := s.ParseOneStmt(sqlStr, "", "")

executor/load_stats.go

@@ -19,6 +19,7 @@ import (
 
 	"github.com/pingcap/errors"
 	"github.com/pingcap/tidb/domain"
+	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/statistics/handle"
 	"github.com/pingcap/tidb/util/chunk"
@@ -85,5 +86,5 @@ func (e *LoadStatsInfo) Update(data []byte) error {
 	if h == nil {
 		return errors.New("Load Stats: handle is nil")
 	}
-	return h.LoadStatsFromJSON(GetInfoSchema(e.Ctx), jsonTbl)
+	return h.LoadStatsFromJSON(infoschema.GetInfoSchema(e.Ctx), jsonTbl)
 }

executor/metrics_test.go

@@ -20,6 +20,7 @@ import (
 	. "github.com/pingcap/check"
 	"github.com/pingcap/parser"
 	"github.com/pingcap/tidb/executor"
+	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/planner"
 	plannercore "github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/sessionctx"
@@ -61,7 +62,7 @@ func (s *testSuite7) TestStmtLabel(c *C) {
 	for _, tt := range tests {
 		stmtNode, err := parser.New().ParseOneStmt(tt.sql, "", "")
 		c.Check(err, IsNil)
-		is := executor.GetInfoSchema(tk.Se)
+		is := infoschema.GetInfoSchema(tk.Se)
 		err = plannercore.Preprocess(tk.Se.(sessionctx.Context), stmtNode, is)
 		c.Assert(err, IsNil)
 		_, _, err = planner.Optimize(context.TODO(), tk.Se, stmtNode, is)

executor/prepared.go

@@ -297,7 +297,7 @@ func CompileExecutePreparedStmt(ctx context.Context, sctx sessionctx.Context,
 		return nil, err
 	}
 	execStmt.BinaryArgs = args
-	is := GetInfoSchema(sctx)
+	is := infoschema.GetInfoSchema(sctx)
 	execPlan, names, err := planner.Optimize(ctx, sctx, execStmt, is)
 	if err != nil {
 		return nil, err