MySQL - 选择字段值不唯一的所有行

Question

如何在MySQL中选择特定字段值不唯一的所有行。例如，我有以下数据：

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| ID | Name   |         URL           |
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| 1  | Store 1| http://www.store1.com |
| 2  | Store 2| http://www.store1.com |
| 3  | Store 3| http://www.store3.com |
| 4  | Store 4| http://www.store4.com |
| 5  | Store 5| http://www.store4.com |
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在此我想要返回URL字段有重复的以下内容：

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| ID | Name   |         URL           |
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| 1  | Store 1| http://www.store1.com |
| 2  | Store 2| http://www.store1.com |
| 4  | Store 4| http://www.store4.com |
| 5  | Store 5| http://www.store4.com |
---------------------------------------

Answer 1

或，老派......

SELECT DISTINCT x.* 
           FROM my_table x 
           JOIN my_table y 
             ON y.url = x.url 
            AND y.id <> x.id 
          ORDER 
             BY id;

Answer 2

如果您想要所有原始行，请使用exists：

select t.*
from table t
where exists (select 1 from table t2 where t2.url = t.url and t2.id <> t.id);

Answer 3

您可以内部联接到您的副本。

select t.* 
from table t
inner join
(select url from table group by 1 having count(*)>1) duplicates
on duplicates.url=t.url