Mysql去除重復值列，只保留一條

Mysql去除重復值列，只保留一條  

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DELETE
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FROM
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      software USING (software,(SELECT DISTINCT min(id) AS id, ident FROM software GROUP BY ident HAVING count(1) > 1) AS t2)
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WHERE
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      software.ident = t2.ident
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AND software.id > t2.id;