-a, --analyze Analyze distribution of keys. Will make some joins in MySQL faster. You can check the calculated distribution. -b, --block-search=# No help available. -B, --backup Make a backup of the .MYD file as 'filename-time.BAK'. --character-sets-dir=name Directory where character sets are. -c, --check Check table for errors. -C, --check-only-changed Check only tables that have changed since last check. It also applies to other requested actions (e.g. --analyze will be ignored if the table is already analyzed). --correct-checksum Correct checksum information for table. --create-missing-keys Create missing keys. This assumes that the data file is correct and that the number of rows stored in the index file is correct. Enables --quick -d, --description Prints some information about table. -D, --data-file-length=# Max length of data file (when recreating data-file when it's full). -e, --extend-check If used when checking a table, ensure that the table is 100 percent consistent, which will take a long time. If used when repairing a table, try to recover every possible row from the data file. Normally this will also find a lot of garbage rows; Don't use this option with repair if you are not totally desperate. -F, --fast Check only tables that haven't been closed properly. It also applies to other requested actions (e.g. --analyze will be ignored if the table is already analyzed). -f, --force Restart with -r if there are any errors in the table. States will be updated as with --update-state. -H, --HELP Display this help and exit. -?, --help Display this help and exit. -i, --information Print statistics information about table that is checked. -k, --keys-used=# Tell MyISAM to update only some specific keys. # is a bit mask of which keys to use. This can be used to get faster inserts. See also keys-active --keys-active=name Treat all not listed keys as disabled. If used with repair, the keys will be disabled permanently. The argument is a list of key numbers, starting from 1, separated by ','. keys-active and keys-used are two ways to do the same thing --max-record-length=# Skip rows bigger than this if myisamchk can't allocate memory to hold it -m, --medium-check Faster than extend-check, but only finds 99.99% of all errors. Should be good enough for most cases. -q, --quick Faster repair by not modifying the data file. -T, --read-only Don't mark table as checked. -r, --recover Can fix almost anything except unique keys that aren't unique. -p, --parallel-recover Same as '-r' but creates all the keys in parallel. -o, --safe-recover Uses old recovery method; Slower than '-r' but can handle a couple of cases where '-r' reports that it can't fix the data file. -n, --sort-recover Force recovering with sorting even if the temporary file was very big. -A, --set-auto-increment[=#] Force auto_increment to start at this or higher value. If no value is given, then sets the next auto_increment value to the highest used value for the auto key + 1. --set-collation=name Change the collation used by the index -s, --silent Only print errors. One can use two -s to make myisamchk very silent. -S, --sort-index Sort index blocks. This speeds up 'read-next' in applications. -R, --sort-records=# Sort records according to an index. This makes your data much more localized and may speed up things. (It may be VERY slow to do a sort the first time!) -t, --tmpdir=name Path for temporary files. -U, --update-state Mark tables as crashed if any errors were found. -u, --unpack Unpack file packed with myisampack. -v, --verbose Print more information. This can be used with --description and --check. Use many -v for more verbosity! -V, --version Print version and exit. -w, --wait Wait if table is locked. --key-buffer-size=# --key-cache-block-size=# --myisam-block-size=# --read-buffer-size=# --write-buffer-size=# --sort-buffer-size=# Deprecated. myisam_sort_buffer_size alias is being used --myisam-sort-buffer-size=# Alias of sort_buffer_size parameter --sort-key-blocks=# --decode-bits=# --ft-min-word-len=# --ft-max-word-len=# --ft-stopword-file=name Use stopwords from this file instead of built-in list. --stats-method=name Specifies how index statistics collection code should treat NULLs. Possible values of name are "nulls_unequal" (default behavior for MySQL 4.1/5.0), "nulls_equal" (emulate 4.0 behavior), and "nulls_ignored".