Try this
Code:
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for `tagcontent`
-- ----------------------------
DROP TABLE IF EXISTS `tagcontent`;
CREATE TABLE `tagcontent` (
`tagid` int(10) unsigned NOT NULL default '0',
`contenttypeid` int(10) unsigned NOT NULL,
`contentid` int(10) unsigned NOT NULL default '0',
`userid` int(10) unsigned NOT NULL default '0',
`dateline` int(10) unsigned NOT NULL default '0',
PRIMARY KEY (`tagid`,`contenttypeid`,`contentid`),
KEY `id_type_user` (`contentid`,`contenttypeid`,`userid`),
KEY `user` (`userid`),
KEY `dateline` (`dateline`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;