MySQL :: MySQL 8.4 Reference Manual :: 6.6.4.2 myisamchk Check Options (original) (raw)

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myisamchk supports the following options for table checking operations:

--check,-c

Command-Line Format --check

Check the table for errors. This is the default operation if you specify no option that selects an operation type explicitly.
--check-only-changed,-C

Command-Line Format --check-only-changed

Check only tables that have changed since the last check.

Command-Line Format	--check
Check the table for errors. This is the default operation if you specify no option that selects an operation type explicitly.

Command-Line Format	--check-only-changed
Check only tables that have changed since the last check.

Command-Line Format	--extend-check
Check the table very thoroughly. This is quite slow if the table has many indexes. This option should only be used in extreme cases. Normally, myisamchk ormyisamchk --medium-check should be able to determine whether there are any errors in the table.
If you are using--extend-check and have plenty of memory, setting the`key_buffer_size` variable to a large value helps the repair operation run faster.
See also the description of this option under table repair options.
For a description of the output format, seeSection 6.6.4.5, “Obtaining Table Information with myisamchk”.

--fast,-F

Command-Line Format --fast

Check only tables that haven't been closed properly.
--force,-f

Command-Line Format --force

Do a repair operation automatically ifmyisamchk finds any errors in the table. The repair type is the same as that specified with the--recover or-r option.
--information,-i

Command-Line Format --information

Print informational statistics about the table that is checked.
--medium-check,-m

Command-Line Format --medium-check

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

Command-Line Format	--fast
Check only tables that haven't been closed properly.

Command-Line Format	--force
Do a repair operation automatically ifmyisamchk finds any errors in the table. The repair type is the same as that specified with the--recover or`-r` option.

Command-Line Format	--information
Print informational statistics about the table that is checked.

Command-Line Format	--medium-check
Do a check that is faster than an--extend-check operation. This finds only 99.99% of all errors, which should be good enough in most cases.

Command-Line Format	--read-only
Do not mark the table as checked. This is useful if you usemyisamchk to check a table that is in use by some other application that does not use locking, such asmysqld when run with external locking disabled.

Command-Line Format	--update-state
Store information in the `.MYI` file to indicate when the table was checked and whether the table crashed. This should be used to get full benefit of the--check-only-changed option, but you shouldn't use this option if themysqld server is using the table and you are running it with external locking disabled.