FLUSH
Syntax
FLUSH [NO_WRITE_TO_BINLOG | LOCAL] flush_option [, flush_option] ...
Description
The FLUSH
statement clears or reloads various internal caches used by
MariaDB. To execute FLUSH
, you must have the RELOAD
privilege. See GRANT
.
The RESET
statement is similar to FLUSH
. See
RESET
.
You cannot issue a FLUSH statement from within a stored function or a trigger. Doing so within a stored procedure is permitted, as long as it is not called by a stored function or trigger. See Stored Routine Limitations, Stored Function Limitations and Trigger Limitations.
By default, FLUSH
statements are written to the binary log and will be replicated. The NO_WRITE_TO_BINLOG
keyword (LOCAL
is an alias) will ensure the statement is not written to the binary log.
The different flush options are:
Option | Description |
---|---|
CLIENT_STATISTICS | Reset client statistics (see 'show client_statistics'). |
DES_KEY_FILE | Reloads the DES key file (Specified with the --des-key-file startup option). |
HOSTS | Flush the hostname cache (used for converting ip to host names and for unblocking blocked hosts. See max_connect_errors) |
INDEX_STATISTICS | Reset index statistics (see 'show index_statistics'). |
LOGS | Close and reopen all logs. Causes binary logs to rotate. |
MASTER | Depricated option, use RESET MASTER instead. |
PRIVILEGES | Reload all privileges from the privilege tables in the 'mysql' database. |
QUERY CACHE | Defragment the query cache to better utilize its memory. If you want to reset the query cache, you can do it with RESET QUERY CACHE. |
SLAVE | Depricated option, use RESET SLAVE instead. |
SLOW QUERY LOGS | Close and reopen the slow query log (but not other logs) |
STATUS | Resets all status variables that can be reset to 0 |
TABLE | Close all open tables. |
TABLES WITH READ LOCK | Closes all open tables. New tables are only allowed to be opened with read locks until an UNLOCK TABLES is given. |
TABLES WITH READ LOCK AND DISABLE CHECKPOINT | As TABLES WITH READ LOCK but also disable all checkpoint writes by transactional table engines. This is usefull when doing a disk snapshot of all tables. |
TABLE_STATISTICS | Reset table statistics (see 'show table_statistics'). |
USER_RESOURCES | Resets all per hour user resources. This enables clients that have exchausted their resources to connect again. |
USER_STATISTICS | Reset user statistics (see 'show user_statistics'). |
You can also use the mysqladmin
client to flush things. Use mysqladmin --help
to examine what flush commands it supports.