Форум пользователей MySQL

CREATE TABLE IF NOT EXISTS `tbl` (
  `uid` int(10) unsigned NOT NULL,
  `id` int(10) unsigned NOT NULL auto_increment,
  `t` int(11) NOT NULL,
  PRIMARY KEY  (`uid`,`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;

SELECT * FROM `tbl` WHERE `uid`=1 AND `id`=2

id               1
select_type      SIMPLE
table            tbl
type             const
possible_keys    PRIMARY
key              PRIMARY
key_len          8
ref              const,const
rows             1
Extra

SELECT * FROM `tbl` WHERE (`uid`,`id`)=(1,2)

id               1
select_type      SIMPLE
table            tbl
type             ALL
possible_keys
key
key_len
ref
rows             104
Extra            Using where