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mysql 刪除數據,mySQL刪除相同數據的SQL語句怎么寫

錢瀠龍2年前20瀏覽0評論
mysql 刪除數據,mySQL刪除相同數據的SQL語句怎么寫?

如果是重復的內容只保留一條,可以試試 delete from t where id not in ( select id from t group by c1, c2, c3, c4)

如果所有重復的內容都刪掉可以試試 delete from t where id not in ( select id from t group by c1, c2, c3, c4 having count (*) < 2)