如何删除SQL中的重复行？

Question

我想删除使用SQL的重复行，同时留下其中一行。

我想删除重复的行从被称为表“A”由的表：

A.AID, A.BID, A.AName, A.AType, A.APrice. 

在这个表中我有很多的所有数据的重复行正好相隔相同来自A.ID.

我想创建一个查询，它将查找重复项，然后删除重复项，确保其中一行被留下。我正在使用phpMyAdmin和MySQL。

Answer 1

DELETE FROM member 
WHERE id IN (SELECT * 
      FROM (SELECT id FROM member 
        GROUP BY member_id, quiz_num, question_num, answer_num HAVING (COUNT(*) > 1) 
       ) AS A 
      ); 

use group by and count

Answer 2

DELETE FROM 
    YourTable 
WHERE 
    AID NOT IN (SELECT 
        MAX(AID) 
       FROM 
        YourTable 
       GROUP BY 
        BID , 
        AName , 
        AType , 
        APrice); 

Answer 3

考虑下面的查询，这将删除所有重复的行和阻止任何未来的重复行。

ALTER IGNORE TABLE A ADD UNIQUE INDEX index_name (A.AID, A.BID, A.AName, A.AType, A.APrice);