Syntax

KILL [HARD | SOFT] [CONNECTION | QUERY] [thread_id | USER user_name]

The options HARD | SOFT and USER username are new in MariaDB 5.3.2

Description

Each connection to mysqld runs in a separate thread. You can see which threads are running with the SHOW PROCESSLIST statement and kill a thread with the KILL thread_id statement. KILL allows the optional CONNECTION or QUERY modifier:

  • KILL CONNECTION is the same as KILL with no modifier: It terminates the connection associated with the given thread_id.
  • KILL QUERY terminates the statement that the connection is currently executing, but leaves the connection itself intact.

If you have the PROCESS privilege, you can see all threads. If you have the SUPER privilege, you can kill all threads and statements. Otherwise, you can see and kill only your own threads and statements.

The HARD option (default) kills a command ASAP. If you use SOFT, then critical operations that may leave a table in an inconsistent state will not be interrupted. Such operations are:

  • REPAIR and INDEX creation for MyISAM and Aria tables.

KILL ... USER username will kill all connections/queries for a given user. USER can be specified one of the following ways:

  • username (Kill without regard to hostname)
  • username@hostname
  • CURRENT_USER or CURRENT_USER()

Note: You cannot use KILL with the Embedded MySQL Server library because the embedded server merely runs inside the threads of the host application. It does not create any connection threads of its own.

Note: You can also use mysqladmin kill thread_id [,thread_id...] to kill connections. To get a list of running queries, use mysqladmin processlist.

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