Provided by: mariadb-client-core_10.11.8-0ubuntu0.23.10.1_amd64 bug

MARIADB-CHECK(1)                     MariaDB Database System                     MARIADB-CHECK(1)

NAME

       mariadb-check - a table maintenance program (mysqlcheck is now a symlink to mariadb-check)

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. 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.

       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 the MariaDB Knowledge Base 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.

       The use of mysqlcheck with partitioned tables is not supported.

           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 following names can be used to change mysqlcheck default behavior.

       ┌──────────────┬──────────────────────────────────┐
       │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] option file groups.  The -c, -r, -a and -o options are
       exclusive to each other.

       •   --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 line.

       •   --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.

       •   --character-sets-dir=path

           The directory where character sets are installed.

       •   --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-auth=name

           Default authentication client-side plugin to use.

       •   --default-character-set=charset_name

           Use charset_name as the default character set.

       •   --defaults-extra-file=filename

           Set filename as the file to read default options from after the global defaults files
           has been read.  Must be given as first option.

       •   --defaults-file=filename

           Set filename as the file to read default options from, override global defaults files.
           Must be given as first option.

       •   --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 will force using the old, slow,
           repair with keycache method, instead of the much faster repair by sorting.

       •   --fast, -F

           Check only tables that have not been closed properly.

       •   --fix-db-names

           Convert database names to the format used since MySQL 5.1. Only database names that
           contain special characters are affected.

       •   --fix-table-names

           Convert table names (including views) to the format used since MySQL 5.1. Only table
           names that contain special characters are affected.

       •   --flush,

           Flush each table after check. This is useful if you don't want to have the checked
           tables take up space in the caches after the check.

       •   --force, -f

           Continue even if an SQL error occurs.

       •   --host=host_name, -h host_name

           Connect to the MariaDB server on the given host.

       •   --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.

       •   --no-defaults

           Do not read default options from any option file. This must be given as the first
           argument.

       •   --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 one.

           Specifying a password on the command line should be considered insecure. You can use
           an option file to avoid giving the password on the command line.

       •   --persistent, -Z

           Used with ANALYZE TABLE to append the option PERSISENT FOR ALL.

       •   --pipe, -W

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

       •   --plugin-dir=name

            Directory for client-side plugins.

       •   --port=port_num, -P port_num

           The TCP/IP port number to use for the connection.  Forces --protocol=tcp when
           specified on the command line without other connection properties.

       •   --print-defaults

           Print the program argument list and exit.  This must be given as the first argument.

       •   --process-tables

           Perform the requested operation on tables. Defaults to on; use --skip-process-tables
           to disable.

       •   --process-views=val

           Perform the requested operation (only CHECK VIEW or REPAIR VIEW). Possible values are
           NO, YES (correct the checksum, if necessary, add the mariadb-version field),
           UPGRADE_FROM_MYSQL (same as YES and toggle the algorithm MERGE<->TEMPTABLE.

       •   --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.

       •   --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.

       •   --silent, -s

           Silent mode. Print only error messages.

       •   --skip-database=db_name

           Don't process the database (case-sensitive) specified as argument.

       •   --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.  Forces --protocol=socket when specified on the command line
           without other connection properties; on Windows, forces --protocol=pipe.

       •   --ssl

           Enable SSL for connection (automatically enabled with other flags). Disable with
           --skip-ssl.

       •   --ssl-ca=name

           CA file in PEM format (check OpenSSL docs, implies --ssl).

       •   --ssl-capath=name

           CA directory (check OpenSSL docs, implies --ssl).

       •   --ssl-cert=name

           X509 cert in PEM format (check OpenSSL docs, implies --ssl).

       •   --ssl-cipher=name

           SSL cipher to use (check OpenSSL docs, implies --ssl).

       •   --ssl-key=name

           X509 key in PEM format (check OpenSSL docs, implies --ssl).

       •   --ssl-crl=name

           Certificate revocation list (check OpenSSL docs, implies --ssl).

       •   --ssl-crlpath=name

           Certificate revocation list path (check OpenSSL docs, implies --ssl).

       •   --ssl-verify-server-cert

           Verify server's "Common Name" in its cert against hostname used when connecting. This
           option is disabled by default.

       •   --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 MariaDB user name to use when connecting to the server.

       •   --verbose, -v

           Verbose mode. Print information about the various stages of program operation.  Using
           one --verbose option will give you more information about what mysqlcheck is doing.

           Using two --verbose options will also give you connection information.

           Using it 3 times will print out all CHECK, RENAME and ALTER TABLE during the check
           phase.

       •   --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

       Copyright 2007-2008 MySQL AB, 2008-2010 Sun Microsystems, Inc., 2010-2020 MariaDB
       Foundation

       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 02110-1335 USA or see http://www.gnu.org/licenses/.

SEE ALSO

       For more information, please refer to the MariaDB Knowledge Base, available online at
       https://mariadb.com/kb/

AUTHOR

       MariaDB Foundation (http://www.mariadb.org/).

MariaDB 10.11                              15 May 2020                           MARIADB-CHECK(1)