Merge branch 'issue-27177-staging-2' of github.com:w169q169/tidb into…

… issue-27177-staging-2

executor/adapter.go

@@ -338,12 +338,11 @@ func (a *ExecStmt) Exec(ctx context.Context) (_ sqlexec.RecordSet, err error) {
 	}()
 
 	failpoint.Inject("assertStaleTSO", func(val failpoint.Value) {
-		if n, ok := val.(int); ok {
+		if n, ok := val.(int); ok && a.IsStaleness {
 			startTS := oracle.ExtractPhysical(a.SnapshotTS) / 1000
 			if n != int(startTS) {
 				panic(fmt.Sprintf("different tso %d != %d", n, startTS))
 			}
-			failpoint.Return()
 		}
 	})
 	sctx := a.Ctx

executor/builder.go

@@ -2608,6 +2608,7 @@ func (b *executorBuilder) buildIndexLookUpJoin(v *plannercore.PhysicalIndexJoin)
 	for i, col := range v.OuterHashKeys {
 		outerTypes[col.Index] = outerTypes[col.Index].Clone()
 		outerTypes[col.Index].Collate = innerTypes[v.InnerHashKeys[i].Index].Collate
+		outerTypes[col.Index].Flag = col.RetType.Flag
 	}
 
 	var (

executor/index_lookup_join_test.go

@@ -349,6 +349,19 @@ func (s *testSuite5) TestIssue24547(c *C) {
 	tk.MustExec("delete a from a inner join b on a.k1 = b.k1 and a.k2 = b.k2 where b.k2 <> '333'")
 }
 
+func (s *testSuite5) TestIssue27893(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t1")
+	tk.MustExec("drop table if exists t2")
+	tk.MustExec("create table t1 (a enum('x','y'))")
+	tk.MustExec("create table t2 (a int, key(a))")
+	tk.MustExec("insert into t1 values('x')")
+	tk.MustExec("insert into t2 values(1)")
+	tk.MustQuery("select /*+ inl_join(t2) */ count(*) from t1 join t2 on t1.a = t2.a").Check(testkit.Rows("1"))
+	tk.MustQuery("select /*+ inl_hash_join(t2) */ count(*) from t1 join t2 on t1.a = t2.a").Check(testkit.Rows("1"))
+}
+
 func (s *testSuite5) TestPartitionTableIndexJoinAndIndexReader(c *C) {
 	if israce.RaceEnabled {
 		c.Skip("exhaustive types test, skip race test")

executor/stale_txn_test.go

@@ -1014,7 +1014,7 @@ func (s *testStaleTxnSerialSuite) TestStaleReadPrepare(c *C) {
 	c.Assert("execute p1", NotNil)
 }
 
-func (s *testStaleTxnSuite) TestStmtCtxStaleFlag(c *C) {
+func (s *testStaleTxnSerialSuite) TestStmtCtxStaleFlag(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists t")
@@ -1106,3 +1106,41 @@ func (s *testStaleTxnSuite) TestStmtCtxStaleFlag(c *C) {
 		c.Assert(tk.Se.GetSessionVars().StmtCtx.IsStaleness, IsFalse)
 	}
 }
+
+func (s *testStaleTxnSerialSuite) TestStaleSessionQuery(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	// For mocktikv, safe point is not initialized, we manually insert it for snapshot to use.
+	safePointName := "tikv_gc_safe_point"
+	safePointValue := "20160102-15:04:05 -0700"
+	safePointComment := "All versions after safe point can be accessed. (DO NOT EDIT)"
+	updateSafePoint := fmt.Sprintf(`INSERT INTO mysql.tidb VALUES ('%[1]s', '%[2]s', '%[3]s')
+	ON DUPLICATE KEY
+	UPDATE variable_value = '%[2]s', comment = '%[3]s'`, safePointName, safePointValue, safePointComment)
+	tk.MustExec(updateSafePoint)
+	tk.MustExec("use test")
+	tk.MustExec("create table t10 (id int);")
+	tk.MustExec("insert into t10 (id) values (1)")
+	time.Sleep(2 * time.Second)
+	now := time.Now()
+	tk.MustExec(`set @@tidb_read_staleness="-1s"`)
+	// query will use stale read
+	c.Assert(failpoint.Enable("github.com/pingcap/tidb/expression/injectNow", fmt.Sprintf(`return(%d)`, now.Unix())), IsNil)
+	c.Assert(failpoint.Enable("github.com/pingcap/tidb/executor/assertStaleTSO", fmt.Sprintf(`return(%d)`, now.Unix()-1)), IsNil)
+	c.Assert(tk.MustQuery("select * from t10;").Rows(), HasLen, 1)
+	c.Assert(failpoint.Disable("github.com/pingcap/tidb/executor/assertStaleTSO"), IsNil)
+	c.Assert(failpoint.Disable("github.com/pingcap/tidb/expression/injectNow"), IsNil)
+	// begin transaction won't be affected by read staleness
+	tk.MustExec("begin")
+	tk.MustExec("insert into t10(id) values (2);")
+	tk.MustExec("commit")
+	tk.MustExec("insert into t10(id) values (3);")
+	// query will still use staleness read
+	c.Assert(failpoint.Enable("github.com/pingcap/tidb/expression/injectNow", fmt.Sprintf(`return(%d)`, now.Unix())), IsNil)
+	c.Assert(failpoint.Enable("github.com/pingcap/tidb/executor/assertStaleTSO", fmt.Sprintf(`return(%d)`, now.Unix()-1)), IsNil)
+	c.Assert(tk.MustQuery("select * from t10").Rows(), HasLen, 1)
+	c.Assert(failpoint.Disable("github.com/pingcap/tidb/executor/assertStaleTSO"), IsNil)
+	c.Assert(failpoint.Disable("github.com/pingcap/tidb/expression/injectNow"), IsNil)
+	// assert stale read is not exist after empty the variable
+	tk.MustExec(`set @@tidb_read_staleness=""`)
+	c.Assert(tk.MustQuery("select * from t10").Rows(), HasLen, 3)
+}