昨天把我的一个dz论坛从X2升级到X2.5出现了问题，升级陷入死循环，具体提示如下：

　　update.php?step=waitingdb&nextstep=prepare& sql[]=5786554789722f09b8f635c20410e507& sql[]=ee4f20b8582052367f5beb9bd19fea58]正在升级数据，请稍后...

　　[时长]:113[状态]:copy to tmp table[信息]:ALTER TABLE pre_forum_post ORDER BY pid ASC

　　[时长]:113[状态]:Locked[信息]:ALTER TABLE pre_forum_post CHANGE `pid` `pid` INT(10) UNSIGNED NOT NULL, CHANGE `replycredit` `replycredit` int(10) NOT NULL default '0', CHANGE `status` `status` int(10) NOT NULL default '0', ADD UNIQUE KEY pid (pid), DROP PRIMARY KEY, ADD `position` INT(8) UNSIGNED NOT NULL AUTO_INCREMENT, ADD PRIMARY KEY(`tid`, `position`), DROP INDEX authorid, ADD INDEX authorid (authorid,invisible)

　　(跳转中...)