execution: fix the incorrect use of cached plan for point get (#24749)

pingcap · May 19, 2021 · f71fbdb · f71fbdb
1 parent 8fb29eb
commit f71fbdb
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Showing 2 changed files with 59 additions and 1 deletion.
diff --git a/session/session.go b/session/session.go
@@ -1820,7 +1820,7 @@ func (s *session) IsCachedExecOk(ctx context.Context, preparedStmt *plannercore.
 		return false, nil
 	}
 	// check auto commit
-	if !s.GetSessionVars().IsAutocommit() {
+	if !plannercore.IsAutoCommitTxn(s) {
 		return false, nil
 	}
 	// check schema version

diff --git a/session/session_test.go b/session/session_test.go
@@ -4485,3 +4485,61 @@ func (s *testSessionSuite) TestReadDMLBatchSize(c *C) {
 	_, _ = se.Execute(context.TODO(), "select 1")
 	c.Assert(se.GetSessionVars().DMLBatchSize, Equals, 1000)
 }
+
+func (s *testSessionSuite) TestInTxnPSProtoPointGet(c *C) {
+	ctx := context.Background()
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("create table t1(c1 int primary key, c2 int, c3 int)")
+	tk.MustExec("insert into t1 values(1, 10, 100)")
+
+	// Generate the ps statement and make the prepared plan cached for point get.
+	id, _, _, err := tk.Se.PrepareStmt("select c1, c2 from t1 where c1 = ?")
+	c.Assert(err, IsNil)
+	idForUpdate, _, _, err := tk.Se.PrepareStmt("select c1, c2 from t1 where c1 = ? for update")
+	c.Assert(err, IsNil)
+	params := []types.Datum{types.NewDatum(1)}
+	rs, err := tk.Se.ExecutePreparedStmt(ctx, id, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 10"))
+	rs, err = tk.Se.ExecutePreparedStmt(ctx, idForUpdate, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 10"))
+
+	// Query again the cached plan will be used.
+	rs, err = tk.Se.ExecutePreparedStmt(ctx, id, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 10"))
+	rs, err = tk.Se.ExecutePreparedStmt(ctx, idForUpdate, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 10"))
+
+	// Start a transaction, now the in txn flag will be added to the session vars.
+	_, err = tk.Se.Execute(ctx, "start transaction")
+	c.Assert(err, IsNil)
+	rs, err = tk.Se.ExecutePreparedStmt(ctx, id, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 10"))
+	txn, err := tk.Se.Txn(false)
+	c.Assert(err, IsNil)
+	c.Assert(txn.Valid(), IsTrue)
+	rs, err = tk.Se.ExecutePreparedStmt(ctx, idForUpdate, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 10"))
+	txn, err = tk.Se.Txn(false)
+	c.Assert(err, IsNil)
+	c.Assert(txn.Valid(), IsTrue)
+	_, err = tk.Se.Execute(ctx, "update t1 set c2 = c2 + 1")
+	c.Assert(err, IsNil)
+	// Check the read result after in-transaction update.
+	rs, err = tk.Se.ExecutePreparedStmt(ctx, id, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 11"))
+	rs, err = tk.Se.ExecutePreparedStmt(ctx, idForUpdate, params)
+	c.Assert(err, IsNil)
+	tk.ResultSetToResult(rs, Commentf("%v", rs)).Check(testkit.Rows("1 11"))
+	txn, err = tk.Se.Txn(false)
+	c.Assert(err, IsNil)
+	c.Assert(txn.Valid(), IsTrue)
+	tk.MustExec("commit")
+}