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MYSQLCHECK(1)		     MySQL Database System		 MYSQLCHECK(1)

NAME
       mysqlcheck - a table maintenance	program

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

DESCRIPTION
       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 14.3.5, "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	14.7.2,	"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
	   test.t
	   note	    : The storage engine for the table doesn't support check

       If mysqlcheck is	unable to repair a table, see Section 2.11.4,
       "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
       TABLE.

	   Caution
	   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. For	information about option files used by MySQL programs,
       see Section 5.2.6, "Using Option	Files".

       o   --help, -?

	   Display a help message and exit.

       o   --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
	   line, except	that the INFORMATION_SCHEMA and	performace_schema
	   databases are not checked. They can be checked by explicitly	naming
	   them	with the --databases option.

       o   --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.

       o   --analyze, -a

	   Analyze the tables.

       o   --auto-repair

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

       o   --bind-address=ip_address

	   On a	computer having	multiple network interfaces, use this option
	   to select which interface to	use for	connecting to the MySQL
	   server.

       o   --character-sets-dir=dir_name

	   The directory where character sets are installed. See Section 11.5,
	   "Character Set Configuration".

       o   --check, -c

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

       o   --check-only-changed, -C

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

       o   --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.

       o   --compress

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

       o   --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 any	following names	as table names.	With this option, it
	   treats all name arguments as	database names.

       o   --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.

       o   --debug-check

	   Print some debugging	information when the program exits.

       o   --debug-info

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

       o   --default-character-set=charset_name

	   Use charset_name as the default character set. See Section 11.5,
	   "Character Set Configuration".

       o   --defaults-extra-file=file_name

	   Read	this option file after the global option file but (on Unix)
	   before the user option file.	If the file does not exist or is
	   otherwise inaccessible, an error occurs.  file_name is interpreted
	   relative to the current directory if	given as a relative path name
	   rather than a full path name.

       o   --defaults-file=file_name

	   Use only the	given option file. If the file does not	exist or is
	   otherwise inaccessible, an error occurs.  file_name is interpreted
	   relative to the current directory if	given as a relative path name
	   rather than a full path name.

	   Exception: Even with	--defaults-file, client	programs read
	   .mylogin.cnf.

       o   --defaults-group-suffix=str

	   Read	not only the usual option groups, but also groups with the
	   usual names and a suffix of str. For	example, mysqlcheck normally
	   reads the [client] and [mysqlcheck] groups. If the
	   --defaults-group-suffix=_other option is given, mysqlcheck also
	   reads the [client_other] and	[mysqlcheck_other] groups.

       o   --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!

       o   --default-auth=plugin

	   A hint about	the client-side	authentication plugin to use. See
	   Section 7.3.8, "Pluggable Authentication".

       o   --enable-cleartext-plugin

	   Enable the mysql_clear_password cleartext authentication plugin.
	   (See	Section	7.5.1.8, "The Cleartext	Client-Side Authentication
	   Plugin".)

	   This	option was added in MySQL 5.7.10.

       o   --fast, -F

	   Check only tables that have not been	closed properly.

       o   --fix-db-names

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

	   This	option is deprecated in	MySQL 5.7.6 and	will be	removed	in a
	   future version of MySQL. If it is necessary to convert MySQL	5.0
	   database or table names, a workaround is to upgrade a MySQL 5.0
	   installation	to MySQL 5.1 before upgrading to a more	recent
	   release.

       o   --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.

	   This	option is deprecated in	MySQL 5.7.6 and	will be	removed	in a
	   future version of MySQL. If it is necessary to convert MySQL	5.0
	   database or table names, a workaround is to upgrade a MySQL 5.0
	   installation	to MySQL 5.1 before upgrading to a more	recent
	   release.

       o   --force, -f

	   Continue even if an SQL error occurs.

       o   --host=host_name, -h	host_name

	   Connect to the MySQL	server on the given host.

       o   --login-path=name

	   Read	options	from the named login path in the .mylogin.cnf login
	   path	file. A	"login path" is	an option group	containing options
	   that	specify	which MySQL server to connect to and which account to
	   authenticate	as. To create or modify	a login	path file, use the
	   mysql_config_editor utility.	See mysql_config_editor(1).

       o   --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
	   cases.

       o   --no-defaults

	   Do not read any option files. If program startup fails due to
	   reading unknown options from	an option file,	--no-defaults can be
	   used	to prevent them	from being read.

	   The exception is that the .mylogin.cnf file,	if it exists, is read
	   in all cases. This permits passwords	to be specified	in a safer way
	   than	on the command line even when --no-defaults is used.
	   (.mylogin.cnf is created by the mysql_config_editor utility.	See
	   mysql_config_editor(1).)

       o   --optimize, -o

	   Optimize the	tables.

       o   --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
	   one.

	   Specifying a	password on the	command	line should be considered
	   insecure. See Section 7.1.2.1, "End-User Guidelines for Password
	   Security". You can use an option file to avoid giving the password
	   on the command line.

       o   --pipe, -W

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

       o   --plugin-dir=dir_name

	   The directory in which to look for plugins. Specify this option if
	   the --default-auth option is	used to	specify	an authentication
	   plugin but mysqlcheck does not find it. See Section 7.3.8,
	   "Pluggable Authentication".

       o   --port=port_num, -P port_num

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

       o   --print-defaults

	   Print the program name and all options that it gets from option
	   files.

       o   --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 5.2.2, "Connecting to the MySQL
	   Server".

       o   --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.

       o   --repair, -r

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

       o   --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 was added in MySQL 5.7.4.

	   As of MySQL 5.7.5, this option is deprecated	and will be removed in
	   a future MySQL release. It is always	enabled	and attempting to
	   disable it (--skip-secure-auth, --secure-auth=0) produces an	error.
	   Before MySQL	5.7.5, this option is enabled by default but can be
	   disabled.

	       Note
	       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	is removed in MySQL 5.7.5. For account upgrade
	       instructions, see Section 7.5.1.3, "Migrating Away from Pre-4.1
	       Password	Hashing	and the	mysql_old_password Plugin".

       o   --shared-memory-base-name=name

	   On Windows, the shared-memory name to use, for connections made
	   using shared	memory to a local server. The default value is MYSQL.
	   The shared-memory name is case sensitive.

	   The server must be started with the --shared-memory option to
	   enable shared-memory	connections.

       o   --silent, -s

	   Silent mode.	Print only error messages.

       o   --skip-database=db_name

	   Do not include the named database (case sensitive) in the
	   operations performed	by mysqlcheck.

       o   --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.

       o   --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 7.4.5, "Command Options for Secure
	   Connections".

       o   --tables

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

       o   --tls-version=protocol_list

	   The protocols permitted by the client for encrypted connections.
	   The value is	a comma-separated list containing one or more protocol
	   names. The protocols	that can be named for this option depend on
	   the SSL library used	to compile MySQL. For details, see
	   Section 7.4.3, "Secure Connection Protocols and Ciphers".

	   This	option was added in MySQL 5.7.10.

       o   --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.

       o   --user=user_name, -u	user_name

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

       o   --verbose, -v

	   Verbose mode. Print information about the various stages of program
	   operation.

       o   --version, -V

	   Display version information and exit.

       o   --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
       Copyright (C) 1997, 2016, Oracle	and/or its affiliates. All rights
       reserved.

       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
       MERCHANTABILITY or FITNESS FOR A	PARTICULAR PURPOSE. See	the GNU
       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
       http://www.gnu.org/licenses/.

SEE ALSO
       For more	information, please refer to the MySQL Reference Manual, which
       may already be installed	locally	and which is also available online at
       http://dev.mysql.com/doc/.

AUTHOR
       Oracle Corporation (http://dev.mysql.com/).

MySQL 5.7			  09/28/2016			 MYSQLCHECK(1)

NAME | SYNOPSIS | DESCRIPTION | COPYRIGHT | SEE ALSO | AUTHOR

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