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(mysql.info)Character sets

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The Character Set Used for Data and Sorting
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By default, MySQL uses the ISO-8859-1 (Latin1) character set with
sorting according to Swedish/Finnish. This is the character set suitable
in the USA and western Europe.

All standard MySQL binaries are compiled with
`--with-extra-charsets=complex'.  This will add code to all standard
programs to be able to handle `latin1' and all multi-byte character
sets within the binary. Other character sets will be loaded from a
character-set definition file when needed.

The character set determines what characters are allowed in names and
how things are sorted by the `ORDER BY' and `GROUP BY' clauses of the
`SELECT' statement.

You can change the character set with the `--default-character-set'
option when you start the server.  The character sets available depend
on the `--with-charset=charset' and `--with-extra-charset=
list-of-charset | complex | all' options to `configure', and the
character set configuration files listed in `SHAREDIR/charsets/Index'.
Note: configure options.

If you change the character set when running MySQL (which may also
change the sort order), you must run myisamchk -r -q on all tables.
Otherwise your indexes may not be ordered correctly.

When a client connects to a MySQL server, the server sends the default
character set in use to the client.  The client will switch to use this
character set for this connection.

One should use `mysql_real_escape_string()' when escaping strings for a
SQL query.  `mysql_real_escape_string()' is identical to the old
`mysql_escape_string()' function, except that it takes the MYSQL
connection handle as the first parameter.

If the client is compiled with different paths than where the server is
installed and the user who configured MySQL didn't included all
character sets in the MySQL binary, one must specify for the client
where it can find the additional character sets it will need if the
server runs with a different character set than the client.

One can specify this by putting in a MySQL option file:

     [client]
     character-sets-dir=/usr/local/mysql/share/mysql/charsets

where the path points to where the dynamic MySQL character sets are
stored.

One can force the client to use specific character set by specifying:

     [client]
     default-character-set=character-set-name

but normally this is never needed.