删除mysql中重复数据，仅保留1行

尝试了百度搜到的前几个答案，没一个可用。注意:c1,c2是用来判断重复的条件。

DELETE FROM table

WHERE id NOT IN(

SELECT id FROM

(

    SELECT MIN(id)AS id

    FROM table

    GROUP BY c1,c2 HAVING

    COUNT(*) > 1

)AS a )

AND id NOT IN(

(SELECT ids FROM

(

SELECT MIN(id)AS ids

    FROM table

    GROUP BY c1,c2 HAVING

    COUNT(*) =1

)AS a1

)

)