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CerebroSQL

MySQL: 

FLUSH

Syntax:
FLUSH [NO_WRITE_TO_BINLOG | LOCAL] {
flush_option [, flush_option] ...
| tables_option
}

flush_option: {
BINARY LOGS
| ENGINE LOGS
| ERROR LOGS
| GENERAL LOGS
| HOSTS
| LOGS
| PRIVILEGES
| OPTIMIZER_COSTS
| RELAY LOGS [FOR CHANNEL channel]
| SLOW LOGS
| STATUS
| USER_RESOURCES
}

tables_option: {
TABLES
| TABLES tbl_name [, tbl_name] ...
| TABLES WITH READ LOCK
| TABLES tbl_name [, tbl_name] ... WITH READ LOCK
| TABLES tbl_name [, tbl_name] ... FOR EXPORT
}

The FLUSH statement has several variant forms that clear or reload
various internal caches, flush tables, or acquire locks. To execute
FLUSH, you must have the RELOAD privilege. Specific flush options might
require additional privileges, as described later.

*Note*:

It is not possible to issue FLUSH statements within stored functions or
triggers. However, you may use FLUSH in stored procedures, so long as
these are not called from stored functions or triggers.

By default, the server writes FLUSH statements to the binary log so
that they replicate to replicas. To suppress logging, specify the
optional NO_WRITE_TO_BINLOG keyword or its alias LOCAL.

*Note*:

FLUSH LOGS, FLUSH BINARY LOGS, FLUSH TABLES WITH READ LOCK (with or
without a table list), and FLUSH TABLES tbl_name ... FOR EXPORT are not
written to the binary log in any case because they would cause problems
if replicated to a replica.

The FLUSH statement causes an implicit commit.

The mysqladmin utility provides a command-line interface to some flush
operations, using commands such as flush-hosts, flush-logs,
flush-privileges, flush-status, and flush-tables.

Sending a SIGHUP or SIGUSR1 signal to the server causes several flush
operations to occur that are similar to various forms of the FLUSH
statement. Signals can be sent by root or the account that owns the
server process. They enable the applicable flush operations to be
performed without having to connect to the server (which for these
operations requires an account that has the RELOAD privilege).
The RESET statement is similar to FLUSH. See [HELP RESET], for
information about using the RESET statement with replication.

Example

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