在MySQL中查找重复的记录

我想在MySQL数据库中取出重复的记录。这可以用:

SELECT address, count(id) as cnt FROM list
GROUP BY address HAVING cnt > 1

结果是:

100 MAIN ST    2

我想要拖动它，以便它显示复制的每一行。喜欢的东西:

JIM    JONES    100 MAIN ST
JOHN   SMITH    100 MAIN ST

有什么想法可以做到吗?我试图避免做第一个，然后在代码中用第二个查询查找重复。

当前回答

select `cityname` from `codcities` group by `cityname` having count(*)>=2

这是你问的类似的问题，它是200%的工作和简单。享受! !

其他回答

 SELECT firstname, lastname, address FROM list
 WHERE 
 Address in 
 (SELECT address FROM list
 GROUP BY address
 HAVING count(*) > 1)

我们也可以发现重复依赖于不止一个字段。对于这些情况，您可以使用下面的格式。

SELECT COUNT(*), column1, column2 
FROM tablename
GROUP BY column1, column2
HAVING COUNT(*)>1;

select `cityname` from `codcities` group by `cityname` having count(*)>=2

这是你问的类似的问题，它是200%的工作和简单。享受! !

不是很有效，但应该可以工作:

SELECT *
FROM list AS outer
WHERE (SELECT COUNT(*)
        FROM list AS inner
        WHERE inner.address = outer.address) > 1;

select * from table_name t1 inner join (select distinct <attribute list> from table_name as temp)t2 where t1.attribute_name = t2.attribute_name

对于你的桌子来说，应该是这样的

select * from list l1 inner join (select distinct address from list as list2)l2 where l1.address=l2.address

这个查询将为您提供列表表中所有不同的地址条目…我不知道这将如何工作，如果你有任何主键值的名称等。

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