This statement is included for compatibility with MySQL. It has no effective usage in TiDB.
mysql> FLUSH TABLES; Query OK, 0 rows affected (0.00 sec) mysql> FLUSH TABLES WITH READ LOCK; ERROR 1105 (HY000): FLUSH TABLES WITH READ LOCK is not supported. Please use @@tidb_snapshot
FLUSH TABLESis parsed but ignored in TiDB for compatibility.
FLUSH TABLES WITH READ LOCKproduces an error, as TiDB does not currently support locking tables. It is recommended to use [Historical reads] for this purpose instead.