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MYSQLCHECK(1)		     MySQL Database System		 MYSQLCHECK(1)

       mysqlcheck - a table maintenance program

       mysqlcheck [options] [db_name [tbl_name ...]]

       The mysqlcheck client performs table maintenance: It checks, repairs,
       optimizes, or analyzes tables.

       Each table is locked and therefore unavailable to other sessions while
       it is being processed, although for check operations, the table is
       locked with a READ lock only (see Section 13.3.5, “LOCK TABLES and
       UNLOCK TABLES Syntax”, for more information about READ and WRITE
       locks). Table maintenance operations can be time-consuming,
       particularly for large tables. If you use the --databases or
       --all-databases option to process all tables in one or more databases,
       an invocation of mysqlcheck might take a long time. (This is also true
       for mysql_upgrade because that program invokes mysqlcheck to check all
       tables and repair them if necessary.)

       mysqlcheck is similar in function to myisamchk, but works differently.
       The main operational difference is that mysqlcheck must be used when
       the mysqld server is running, whereas myisamchk should be used when it
       is not. The benefit of using mysqlcheck is that you do not have to stop
       the server to perform table maintenance.

       mysqlcheck uses the SQL statements CHECK TABLE, REPAIR TABLE, ANALYZE
       TABLE, and OPTIMIZE TABLE in a convenient way for the user. It
       determines which statements to use for the operation you want to
       perform, and then sends the statements to the server to be executed.
       For details about which storage engines each statement works with, see
       the descriptions for those statements in Section 13.7.2, “Table
       Maintenance Statements”.

       The MyISAM storage engine supports all four maintenance operations, so
       mysqlcheck can be used to perform any of them on MyISAM tables. Other
       storage engines do not necessarily support all operations. In such
       cases, an error message is displayed. For example, if test.t is a
       MEMORY table, an attempt to check it produces this result:

	   shell> mysqlcheck test t
	   note	    : The storage engine for the table doesn't support check

       If mysqlcheck is unable to repair a table, see Section 2.10.4,
       “Rebuilding or Repairing Tables or Indexes” for manual table repair
       strategies. This will be the case, for example, for InnoDB tables,
       which can be checked with CHECK TABLE, but not repaired with REPAIR

	   It is best to make a backup of a table before performing a table
	   repair operation; under some circumstances the operation might
	   cause data loss. Possible causes include but are not limited to
	   file system errors.

       There are three general ways to invoke mysqlcheck:

	   shell> mysqlcheck [options] db_name [tbl_name ...]
	   shell> mysqlcheck [options] --databases db_name ...
	   shell> mysqlcheck [options] --all-databases

       If you do not name any tables following db_name or if you use the
       --databases or --all-databases option, entire databases are checked.

       mysqlcheck has a special feature compared to other client programs. The
       default behavior of checking tables (--check) can be changed by
       renaming the binary. If you want to have a tool that repairs tables by
       default, you should just make a copy of mysqlcheck named mysqlrepair,
       or make a symbolic link to mysqlcheck named mysqlrepair. If you invoke
       mysqlrepair, it repairs tables.

       The names shown in the following table can be used to change mysqlcheck
       default behavior.

       │Command	      │ Meaning		      │
       │mysqlrepair   │ The default option is │
       │	      │ --repair	      │
       │mysqlanalyze  │ The default option is │
       │	      │ --analyze	      │
       │mysqloptimize │ The default option is │
       │	      │ --optimize	      │

       mysqlcheck supports the following options, which can be specified on
       the command line or in the [mysqlcheck] and [client] groups of an
       option file.  mysqlcheck also supports the options for processing
       option files described at Section, “Command-Line Options that
       Affect Option-File Handling”.

       ·   --help, -?

	   Display a help message and exit.

       ·   --all-databases, -A

	   Check all tables in all databases. This is the same as using the
	   --databases option and naming all the databases on the command

       ·   --all-in-1, -1

	   Instead of issuing a statement for each table, execute a single
	   statement for each database that names all the tables from that
	   database to be processed.

       ·   --analyze, -a

	   Analyze the tables.

       ·   --auto-repair

	   If a checked table is corrupted, automatically fix it. Any
	   necessary repairs are done after all tables have been checked.

       ·   --bind-address=ip_address

	   On a computer having multiple network interfaces, this option can
	   be used to select which interface is employed when connecting to
	   the MySQL server.

	   This option is supported beginning with MySQL 5.6.1.

       ·   --character-sets-dir=path

	   The directory where character sets are installed. See Section 10.5,
	   “Character Set Configuration”.

       ·   --check, -c

	   Check the tables for errors. This is the default operation.

       ·   --check-only-changed, -C

	   Check only tables that have changed since the last check or that
	   have not been closed properly.

       ·   --check-upgrade, -g

	   Invoke CHECK TABLE with the FOR UPGRADE option to check tables for
	   incompatibilities with the current version of the server. This
	   option automatically enables the --fix-db-names and
	   --fix-table-names options.

       ·   --compress

	   Compress all information sent between the client and the server if
	   both support compression.

       ·   --databases, -B

	   Process all tables in the named databases. Normally, mysqlcheck
	   treats the first name argument on the command line as a database
	   name and following names as table names. With this option, it
	   treats all name arguments as database names.

       ·   --debug[=debug_options], -# [debug_options]

	   Write a debugging log. A typical debug_options string is
	   d:t:o,file_name. The default is d:t:o.

       ·   --debug-check

	   Print some debugging information when the program exits.

       ·   --debug-info

	   Print debugging information and memory and CPU usage statistics
	   when the program exits.

       ·   --default-character-set=charset_name

	   Use charset_name as the default character set. See Section 10.5,
	   “Character Set Configuration”.

       ·   --extended, -e

	   If you are using this option to check tables, it ensures that they
	   are 100% consistent but takes a long time.

	   If you are using this option to repair tables, it runs an extended
	   repair that may not only take a long time to execute, but may
	   produce a lot of garbage rows also!

       ·   --default-auth=plugin

	   The client-side authentication plugin to use. See Section 6.3.7,
	   “Pluggable Authentication”.

	   This option was added in MySQL 5.6.2.

       ·   --fast, -F

	   Check only tables that have not been closed properly.

       ·   --fix-db-names

	   Convert database names to 5.1 format. Only database names that
	   contain special characters are affected.

       ·   --fix-table-names

	   Convert table names to 5.1 format. Only table names that contain
	   special characters are affected. This option also applies to views.

       ·   --force, -f

	   Continue even if an SQL error occurs.

       ·   --host=host_name, -h host_name

	   Connect to the MySQL server on the given host.

       ·   --login-path=name

	   Read options from the named login path in the .mylogin.cnf login
	   file. A “login path” is an option group that permits only a limited
	   set of options: host, user, and password. Think of a login path as
	   a set of values that indicate the server host and the credentials
	   for authenticating with the server. To create the login file, use
	   the mysql_config_editor utility. See mysql_config_editor(1). This
	   option was added in MySQL 5.6.6.

       ·   --medium-check, -m

	   Do a check that is faster than an --extended operation. This finds
	   only 99.99% of all errors, which should be good enough in most

       ·   --optimize, -o

	   Optimize the tables.

       ·   --password[=password], -p[password]

	   The password to use when connecting to the server. If you use the
	   short option form (-p), you cannot have a space between the option
	   and the password. If you omit the password value following the
	   --password or -p option on the command line, mysqlcheck prompts for

	   Specifying a password on the command line should be considered
	   insecure. See Section, “End-User Guidelines for Password
	   Security”. You can use an option file to avoid giving the password
	   on the command line.

       ·   --pipe, -W

	   On Windows, connect to the server using a named pipe. This option
	   applies only if the server supports named-pipe connections.

       ·   --plugin-dir=path

	   The directory in which to look for plugins. It may be necessary to
	   specify this option if the --default-auth option is used to specify
	   an authentication plugin but mysqlcheck does not find it. See
	   Section 6.3.7, “Pluggable Authentication”.

	   This option was added in MySQL 5.6.2.

       ·   --port=port_num, -P port_num

	   The TCP/IP port number to use for the connection.

       ·   --protocol={TCP|SOCKET|PIPE|MEMORY}

	   The connection protocol to use for connecting to the server. It is
	   useful when the other connection parameters normally would cause a
	   protocol to be used other than the one you want. For details on the
	   permissible values, see Section 4.2.2, “Connecting to the MySQL

       ·   --quick, -q

	   If you are using this option to check tables, it prevents the check
	   from scanning the rows to check for incorrect links. This is the
	   fastest check method.

	   If you are using this option to repair tables, it tries to repair
	   only the index tree. This is the fastest repair method.

       ·   --repair, -r

	   Perform a repair that can fix almost anything except unique keys
	   that are not unique.

       ·   --secure-auth

	   Do not send passwords to the server in old (pre-4.1) format. This
	   prevents connections except for servers that use the newer password
	   format. This option is enabled by default; use --skip-secure-auth
	   to disable it. This option was added in MySQL 5.6.17.

	       Passwords that use the pre-4.1 hashing method are less secure
	       than passwords that use the native password hashing method and
	       should be avoided. Pre-4.1 passwords are deprecated and support
	       for them will be removed in a future MySQL release. For account
	       upgrade instructions, see Section, “Migrating Away from
	       Pre-4.1 Password Hashing and the mysql_old_password Plugin”.

       ·   --silent, -s

	   Silent mode. Print only error messages.

       ·   --skip-database=db_name

	   Do not include the named database (case sensitive) in the
	   operations performed by mysqlcheck. This option was added in MySQL

       ·   --socket=path, -S path

	   For connections to localhost, the Unix socket file to use, or, on
	   Windows, the name of the named pipe to use.

       ·   --ssl*

	   Options that begin with --ssl specify whether to connect to the
	   server using SSL and indicate where to find SSL keys and
	   certificates. See Section, “SSL Command Options”.

       ·   --tables

	   Override the --databases or -B option. All name arguments following
	   the option are regarded as table names.

       ·   --use-frm

	   For repair operations on MyISAM tables, get the table structure
	   from the .frm file so that the table can be repaired even if the
	   .MYI header is corrupted.

       ·   --user=user_name, -u user_name

	   The MySQL user name to use when connecting to the server.

       ·   --verbose, -v

	   Verbose mode. Print information about the various stages of program

       ·   --version, -V

	   Display version information and exit.

       ·   --write-binlog

	   This option is enabled by default, so that ANALYZE TABLE, OPTIMIZE
	   TABLE, and REPAIR TABLE statements generated by mysqlcheck are
	   written to the binary log. Use --skip-write-binlog to cause
	   NO_WRITE_TO_BINLOG to be added to the statements so that they are
	   not logged. Use the --skip-write-binlog when these statements
	   should not be sent to replication slaves or run when using the
	   binary logs for recovery from backup.

       Copyright © 1997, 2014, Oracle and/or its affiliates. All rights

       This documentation is free software; you can redistribute it and/or
       modify it only under the terms of the GNU General Public License as
       published by the Free Software Foundation; version 2 of the License.

       This documentation is distributed in the hope that it will be useful,
       but WITHOUT ANY WARRANTY; without even the implied warranty of
       General Public License for more details.

       You should have received a copy of the GNU General Public License along
       with the program; if not, write to the Free Software Foundation, Inc.,
       51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see

       For more information, please refer to the MySQL Reference Manual, which
       may already be installed locally and which is also available online at

       Oracle Corporation (

MySQL 5.6			  03/14/2014			 MYSQLCHECK(1)

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