MYSQL删除所有具有count(*)= 1的结果

Question

我有一个表有两个字段sesskey(varchar32,index)和产品(int11)的表,现在我必须删除所有具有group by sesskey count(*)= 1的行.我正在尝试一些方法,但都失败了.

例:

delete from taged where sesskey in (select sesskey from taged group by sesskey having count(*) = 1)

sesskey字段不能成为主键,因为它重复了.

Answer 1

DELETE  si
FROM    t_session si
JOIN    (
        SELECT  sesskey
        FROM    t_session so
        GROUP BY
                sesskey
        HAVING  COUNT(*) = 1
        ) q
ON      q.sesskey = si.sesskey

你需要在这里加入.使用相关子查询将不起作用.

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