论坛发帖出现错求大神指教

Discuz! Database Error(1062) Duplicate entry '7034' for key 'pid'INSERT INTO forum_post SET `fid`='2' , `tid`='7048' , `first`='1' , `author`='admin' , `authorid`='1' , `subject`='法士大夫的说法' , `dateline`='1403410442' , `message`='法士大夫的说法\r\n' , `useip`='175.0.154.202' , `port`='' , `invisible`='0' , `anonymous`='0' , `usesig`='1' , `htmlon`='0' , `bbcodeoff`='-1' , `smileyoff`='-1' , `parseurloff`=0 , `attachment`='0' , `tags`='8450,士大夫 ' , `replycredit`='0' , `status`='0' , `pid`='7034'

PHP Debug

No.	File	Line	Code
1	forum.php	71	require(%s)
2	source/module/forum/forum_post.php	341	require_once(%s)
3	source/include/post/post_newthread.php	279	discuz_container->newthread(%s, Array)
4			discuz_container->__call(Array)
5	source/class/discuz/discuz_container.php	59	model_forum_thread->newthread(Array)
6	source/class/model/model_forum_thread.php	206	insertpost()
7	source/function/function_forum.php	825	table_forum_post->insert(%s, Array)
8	source/class/table/table_forum_post.php	607	discuz_database::insert(%s, Array, false, false, false)
9	source/class/discuz/discuz_database.php	60	discuz_database::query(%s, %s, %s, true)
10	source/class/discuz/discuz_database.php	136	db_driver_mysql->query(%s, %s, true)
11	source/class/db/db_driver_mysql.php	153	db_driver_mysql->halt(%s, %d, %s)
12	source/class/db/db_driver_mysql.php	224	break()

怎么回事 一发帖就出现这个问题  如何解决