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5月, 2011 | 1

查找与删除重复的记录

[ 2011-05-20 17:04:27 | 作者: admin ]
//查找重复的记录
SELECT `loginname` , count( `loginname` ) AS num
FROM nth_member
GROUP BY loginname
ORDER BY num DESC


//删除重复的记录
DELETE nth_member AS a FROM nth_member AS a,
(
SELECT *
FROM nth_member
GROUP BY `loginname`
HAVING count( 1 ) >1
) AS b
WHERE a.loginname = b.loginname
AND a.id > b.id
分类: Mysql | 永久链接 | 评论: 0 | 引用: 0 | 浏览: 1797
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