planner: plan cache always check scheme valid in RC isolation level (#…

…34523) (#34619)

close #34447

executor/adapter.go

@@ -810,7 +810,7 @@ type pessimisticTxn interface {
 	KeysNeedToLock() ([]kv.Key, error)
 }
 
-// buildExecutor build a executor from plan, prepared statement may need additional procedure.
+// buildExecutor build an executor from plan, prepared statement may need additional procedure.
 func (a *ExecStmt) buildExecutor() (Executor, error) {
 	ctx := a.Ctx
 	stmtCtx := ctx.GetSessionVars().StmtCtx

planner/core/planbuilder.go

@@ -1069,6 +1069,7 @@ func getPossibleAccessPaths(ctx sessionctx.Context, tableHints *tableHintInfo, i
 
 	optimizerUseInvisibleIndexes := ctx.GetSessionVars().OptimizerUseInvisibleIndexes
 
+	check = check || ctx.GetSessionVars().IsIsolation(ast.ReadCommitted)
 	check = check && ctx.GetSessionVars().ConnectionID > 0
 	var latestIndexes map[int64]*model.IndexInfo
 	var err error
@@ -1576,7 +1577,8 @@ func (b *PlanBuilder) buildPhysicalIndexLookUpReaders(ctx context.Context, dbNam
 	indexInfos := make([]*model.IndexInfo, 0, len(tblInfo.Indices))
 	indexLookUpReaders := make([]Plan, 0, len(tblInfo.Indices))
 
-	check := b.isForUpdateRead && b.ctx.GetSessionVars().ConnectionID > 0
+	check := b.isForUpdateRead || b.ctx.GetSessionVars().IsIsolation(ast.ReadCommitted)
+	check = check && b.ctx.GetSessionVars().ConnectionID > 0
 	var latestIndexes map[int64]*model.IndexInfo
 	var err error
 

planner/core/point_get_plan.go

@@ -915,6 +915,7 @@ func tryPointGetPlan(ctx sessionctx.Context, selStmt *ast.SelectStmt, check bool
 		return nil
 	}
 
+	check = check || ctx.GetSessionVars().IsIsolation(ast.ReadCommitted)
 	check = check && ctx.GetSessionVars().ConnectionID > 0
 	var latestIndexes map[int64]*model.IndexInfo
 	var err error

planner/core/prepare_test.go

@@ -33,6 +33,7 @@ import (
 	"github.com/pingcap/tidb/planner/core"
 	"github.com/pingcap/tidb/session"
 	"github.com/pingcap/tidb/sessionctx/variable"
+	"github.com/pingcap/tidb/types"
 	"github.com/pingcap/tidb/util/hint"
 	"github.com/pingcap/tidb/util/israce"
 	"github.com/pingcap/tidb/util/kvcache"
@@ -2694,3 +2695,52 @@ func (s *testPlanSerialSuite) TestPartitionWithVariedDatasources(c *C) {
 		}
 	}
 }
+
+func (s *testPlanSerialSuite) TestPlanCacheWithRCWhenInfoSchemaChange(c *C) {
+	store, dom, err := newStoreWithBootstrap()
+	orgEnable := core.PreparedPlanCacheEnabled()
+	defer func() {
+		dom.Close()
+		err = store.Close()
+		c.Assert(err, IsNil)
+		core.SetPreparedPlanCache(orgEnable)
+	}()
+	core.SetPreparedPlanCache(true)
+
+	ctx := context.Background()
+
+	tk1 := testkit.NewTestKit(c, store)
+	tk2 := testkit.NewTestKit(c, store)
+	tk1.MustExec("use test")
+	tk2.MustExec("use test")
+	tk1.MustExec("drop table if exists t1")
+	tk1.MustExec("create table t1(id int primary key, c int, index ic (c))")
+	// prepare text protocol
+	tk1.MustExec("prepare s from 'select /*+use_index(t1, ic)*/ * from t1 where 1'")
+	// prepare binary protocol
+	stmtID, _, _, err := tk2.Se.PrepareStmt("select /*+use_index(t1, ic)*/ * from t1 where 1")
+	c.Assert(err, IsNil)
+	tk1.MustExec("set tx_isolation='READ-COMMITTED'")
+	tk1.MustExec("begin pessimistic")
+	tk2.MustExec("set tx_isolation='READ-COMMITTED'")
+	tk2.MustExec("begin pessimistic")
+	tk1.MustQuery("execute s").Check(testkit.Rows())
+	rs, err := tk2.Se.ExecutePreparedStmt(ctx, stmtID, []types.Datum{})
+	c.Assert(err, IsNil)
+	tk2.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows())
+
+	tk3 := testkit.NewTestKit(c, store)
+	tk3.MustExec("use test")
+	tk3.MustExec("alter table t1 drop index ic")
+	tk3.MustExec("insert into t1 values(1, 0)")
+
+	// The execution after schema changed should not hit plan cache.
+	// execute text protocol
+	tk1.MustQuery("execute s").Check(testkit.Rows("1 0"))
+	tk1.MustQuery("select @@last_plan_from_cache").Check(testkit.Rows("0"))
+	// execute binary protocol
+	rs, err = tk2.Se.ExecutePreparedStmt(ctx, stmtID, []types.Datum{})
+	c.Assert(err, IsNil)
+	tk2.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 0"))
+	tk2.MustQuery("select @@last_plan_from_cache").Check(testkit.Rows("0"))
+}

planner/core/rule_build_key_info.go

@@ -267,8 +267,10 @@ func (ds *DataSource) BuildKeyInfo(selfSchema *expression.Schema, childSchema []
 	var latestIndexes map[int64]*model.IndexInfo
 	var changed bool
 	var err error
+	check := ds.ctx.GetSessionVars().IsIsolation(ast.ReadCommitted) || ds.isForUpdateRead
+	check = check && ds.ctx.GetSessionVars().ConnectionID > 0
 	// we should check index valid while forUpdateRead, see detail in https://github.com/pingcap/tidb/pull/22152
-	if ds.isForUpdateRead {
+	if check {
 		latestIndexes, changed, err = getLatestIndexInfo(ds.ctx, ds.table.Meta().ID, 0)
 		if err != nil {
 			return

planner/optimize.go

@@ -71,7 +71,12 @@ func GetExecuteForUpdateReadIS(node ast.Node, sctx sessionctx.Context) infoschem
 			execID = vars.PreparedStmtNameToID[execStmt.Name]
 		}
 		if preparedPointer, ok := vars.PreparedStmts[execID]; ok {
-			if preparedObj, ok := preparedPointer.(*core.CachedPrepareStmt); ok && preparedObj.ForUpdateRead {
+			checkSchema := vars.IsIsolation(ast.ReadCommitted)
+			if !checkSchema {
+				preparedObj, ok := preparedPointer.(*core.CachedPrepareStmt)
+				checkSchema = ok && preparedObj.ForUpdateRead
+			}
+			if checkSchema {
 				is := domain.GetDomain(sctx).InfoSchema()
 				return temptable.AttachLocalTemporaryTableInfoSchema(sctx, is)
 			}

session/session.go

@@ -2140,6 +2140,9 @@ func (s *session) ExecutePreparedStmt(ctx context.Context, stmtID uint32, args [
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
+	} else if s.sessionVars.IsIsolation(ast.ReadCommitted) || preparedStmt.ForUpdateRead {
+		is = domain.GetDomain(s).InfoSchema()
+		is = temptable.AttachLocalTemporaryTableInfoSchema(s, is)
 	} else {
 		is = s.GetInfoSchema().(infoschema.InfoSchema)
 	}