Nice bugs that no one seems to want to fix:- mysql> create table test5 ( wibble varchar(500), PRIMARY KEY (wibble) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin; ERROR 1071 (42000): Specified key was too long; max key length is 767 bytes mysql> create table test5 ( wibble varchar(500), PRIMARY KEY (wibble) ) ENGINE=myisam DEFAULT CHARSET=utf8 COLLATE=utf8_bin; ERROR 1071 (42000): Specified key was too long; max key length is 1332 bytes And even with MySQL 6.