Syntax:
BACKUP TABLE tbl_name [, tbl_name] ... TO '/path/to/backup/directory'

Note: This statement is deprecated. We are working on a better
replacement for it that will provide online backup capabilities. In the
meantime, the mysqlhotcopy script can be used instead.

BACKUP TABLE copies to the backup directory the minimum number of table
files needed to restore the table, after flushing any buffered changes
to disk. The statement works only for MyISAM tables. It copies the .frm
definition and .MYD data files. The .MYI index file can be rebuilt from
those two files. The directory should be specified as a full pathname.
To restore the table, use RESTORE TABLE.

URL: http://dev.mysql.com/doc/refman/5.0/en/backup-table.html

