FLUSH TABLES
This statement is included for compatibility with MySQL. It has no effective usage in TiDB.
Synopsis
- FlushStmt
- NoWriteToBinLogAliasOpt
- FlushOption
- LogTypeOpt
- TableOrTables
- TableNameListOpt
- WithReadLockOpt
FlushStmt ::=
'FLUSH' NoWriteToBinLogAliasOpt FlushOption
NoWriteToBinLogAliasOpt ::=
( 'NO_WRITE_TO_BINLOG' | 'LOCAL' )?
FlushOption ::=
'PRIVILEGES'
| 'STATUS'
| 'TIDB' 'PLUGINS' PluginNameList
| 'HOSTS'
| LogTypeOpt 'LOGS'
| TableOrTables TableNameListOpt WithReadLockOpt
LogTypeOpt ::=
( 'BINARY' | 'ENGINE' | 'ERROR' | 'GENERAL' | 'SLOW' )?
TableOrTables ::=
'TABLE'
| 'TABLES'
TableNameListOpt ::=
TableNameList?
WithReadLockOpt ::=
( 'WITH' 'READ' 'LOCK' )?
Examples
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
MySQL compatibility
- TiDB does not have a concept of table cache as in MySQL. Thus,
FLUSH TABLES
is parsed but ignored in TiDB for compatibility. - The statement
FLUSH TABLES WITH READ LOCK
produces an error, as TiDB does not currently support locking tables. It is recommended to use Historical reads for this purpose instead.