Display a help message and exit.
Check all tables in all databases. This is the same as
--databases option and naming
all the databases on the command line.
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 the tables.
If a checked table is corrupted, automatically fix it. Any
necessary repairs are done after all tables have been
The directory where character sets are installed. See
Section 5.10.1, “The Character Set Used for Data and Sorting”.
Check the tables for errors. This is the default
Check only tables that have changed since the last check
or that have not been closed properly.
CHECK TABLE with the
FOR UPGRADE option to check tables for
incompatibilities with the current version of the server.
This option automatically enables the
--check-upgrade was added in MySQL 5.1.7.
Compress all information sent between the client and the
server if both support compression.
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.
Write a debugging log. A typical
debug_options string is often
charset_name as the default
character set. See Section 5.10.1, “The Character Set Used for Data and Sorting”.
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!
Check only tables that have not been closed properly.
Convert database names to 5.1 format. Only database names
that contain special characters are affected. This option
was added in MySQL 5.1.7.
Convert table names to 5.1 format. Only table names that
contain special characters are affected. This option was
added in MySQL 5.1.7.
Continue even if an SQL error occurs.
Connect to the MySQL server on the given host.
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
Optimize the tables.
The password to use when connecting to the server. If you
use the short option form (
cannot have a space between the
option and the password. If you omit the
password value following the
on the command line, you are prompted for one.
Specifying a password on the command line should be
considered insecure. See
Section 5.8.6, “Keeping Your Password Secure”.
The TCP/IP port number to use for the connection.
The connection protocol to use.
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
Perform a repair that can fix almost anything except
unique keys that are not unique.
Silent mode. Print only error messages.
For connections to
localhost, the Unix
socket file to use, or, on Windows, the name of the named
pipe to use.
-B option. All name arguments following
the option are regarded as table names.
For repair operations on
get the table structure from the
file so that the table can be repaired even if the
.MYI header is corrupted.
The MySQL username to use when connecting to the server.
Verbose mode. Print information about the various stages
of program operation.
Display version information and exit.