Added documentation about mysqlcheck.

Maintaining a MySQL Installation

* Table maintenance::           Table maintenance and crash recovery

* Using mysqlcheck::            Using mysqlcheck for maintenance and recovery

* Maintenance regimen::         Setting up a table maintenance regimen

* Table-info::                  Getting information about a table

* Crash recovery::              Using @code{myisamchk} for crash recovery

@cindex maintaining, tables

@cindex tables, maintaining

@cindex databases, maintaining

@cindex @code{mysiamchk}

@cindex @code{myisamchk}

@cindex @code{mysqlcheck}

@cindex crash, recovery

@cindex recovery, from crash

@node Maintenance, Adding functions, Tools, Top

@menu

* Table maintenance::           Table maintenance and crash recovery

* Using mysqlcheck::            Using mysqlcheck for maintenance and recovery

* Maintenance regimen::         Setting up a table maintenance regimen

* Table-info::                  Getting information about a table

* Crash recovery::              Using @code{myisamchk} for crash recovery

distribution.  You will learn how to care for your tables on a regular

basis, and what to do when disaster strikes.

@node Table maintenance, Maintenance regimen, Maintenance, Maintenance

@node Table maintenance, Using mysqlcheck, Maintenance, Maintenance

@section Using @code{myisamchk} for Table Maintenance and Crash Recovery

Starting with @strong{MySQL} Version 3.23.13, you can check MyISAM

If you have a problem with disk space during repair, you can try to use

@code{--safe-recover} instead of @code{--recover}.

@node Using mysqlcheck, Maintenance regimen, Table maintenance, Maintenance

@section Using @code{mysqlcheck} for Table Maintenance and Crash Recovery

Since @strong{MySQL} version 3.23.38 you will be able to use a new

checking and repairing tool for @code{MyISAM} tables. The difference to

@code{myisamchk} is that @code{mysqlcheck} should be used when the

@code{mysqld} server is running, where as @code{myisamchk} should be used

when it is not. The benefit is that you no longer have to take the

server down for checking or repairing your tables.

@code{mysqlcheck} uses @strong{MySQL} server commands @code{CHECK},

@code{REPAIR}, @code{ANALYZE} and @code{OPTIMIZE} in a convenient way

for the user.

There are three alternative ways to invoke @code{mysqlcheck}:

@example

shell> mysqlcheck [OPTIONS] database [tables]

shell> mysqlcheck [OPTIONS] --databases DB1 [DB2 DB3...]

shell> mysqlcheck [OPTIONS] --all-databases

@end example

So it can be used in a similar way as @code{mysqldump} when it

comes to what databases and tables you want to choose.

@code{mysqlcheck} does have a special feature compared to the other

clients; the default behavior, checking tables (-c), can be changed by

renaming the binary. So if you want to have a tool that repairs tables

by default, you should just copy @code{mysqlcheck} to your harddrive

with a new name, @code{mysqlrepair}, or alternatively make a symbolic

link to @code{mysqlrepair} and name the symbolic link as

@code{mysqlrepair}. If you invoke @code{mysqlrepair} now, it will repair

tables by default.

The names that you can use to change @code{mysqlcheck} default behavior

are here:

@example

mysqlrepair:   The default option will be -r

mysqlanalyze:  The default option will be -a

mysqloptimize: The default option will be -o

@end example

The options available for @code{mysqlcheck} are listed here, please

check what your version supports with @code{mysqlcheck --help}.

@table @code

@item -A, --all-databases

Check all the databases. This will be same as --databases with all

databases selected

@item -1, --all-in-1

Instead of making one query for each table, execute all queries in 1

query separately for each database. Table names will be in a comma

separated list.

@item  -a, --analyze

Analyze given tables.

@item --auto-repair

If a checked table is corrupted, automatically fix it. Repairing will be

done after all tables have been checked, if corrupted ones were found.

@item -#, --debug=...

Output debug log. Often this is 'd:t:o,filename'

@item --character-sets-dir=...

Directory where character sets are

@item -c, --check

Check table for errors

@item -C, --check-only-changed

Check only tables that have changed since last check or haven't been

closed properly.

@item --compress

Use compression in server/client protocol.

@item -?, --help

Display this help message and exit.

@item -B, --databases

To check several databases. Note the difference in usage; In this case

no tables are given. All name arguments are regarded as database names.

@item --default-character-set=...

Set the default character set

@item -F, --fast

Check only tables that hasn't been closed properly

@item -f, --force

Continue even if we get an sql-error.

@item -e, --extended

If you are using this option with CHECK TABLE, it will ensure that the

table is 100 percent consistent, but will take a long time.

If you are using this option with REPAIR TABLE, it will run an extended

repair on the table, which may not only take a long time to execute, but

may produce a lot of garbage rows also!

@item -h, --host=...

Connect to host.

@item -m, --medium-check

Faster than extended-check, but only finds 99.99 percent of all

errors. Should be good enough for most cases.

@item -o, --optimize

Optimize table

@item -p, --password[=...]

Password to use when connecting to server. If password is not given

it's solicited on the tty.

@item -P, --port=...

Port number to use for connection.

@item -q, --quick

If you are using this option with CHECK TABLE, it prevents the check

from scanning the rows to check for wrong links. This is the fastest

check.

If you are using this option with REPAIR TABLE, it will try to repair

only the index tree. This is the fastest repair method for a table.

@item -r, --repair

Can fix almost anything except unique keys that aren't unique.

@item -s, --silent

Print only error messages.

@item -S, --socket=...

Socket file to use for connection.

@item --tables

Overrides option --databases (-B).

@item -u, --user=#

User for login if not current user.

@item -v, --verbose

Print info about the various stages.

@item -V, --version

Output version information and exit.

@end table

@cindex maintaining, tables

@cindex tables, maintenance regimen

@node Maintenance regimen, Table-info, Table maintenance, Maintenance

@node Maintenance regimen, Table-info, Using mysqlcheck, Maintenance

@section Setting Up a Table Maintenance Regimen

Starting with @strong{MySQL} Version 3.23.13, you can check MyISAM