Question

无论如何，我可以使用group by并具有

来显示mysql中所有重复的值

+---------+--------------+------------+--------+----------+----------+---------+
| ENumber | EmpName      | Birthdate  | Gender | Address  | Salary   | DNumber |
+---------+--------------+------------+--------+----------+----------+---------+
| E001    | GSInocencio  | 1988-01-15 | F      | Munoz    | 18000.00 | D005    |
| E002    | EAVillanueva | 1988-04-20 | F      | Munoz    | 23000.00 | D003    |
| E003    | ALedesma     | 1988-05-25 | M      | CLSU     | 21000.00 | D002    |
| E004    | APGamilla    | 1991-10-15 | F      | Maligaya | 25000.00 | D001    |
| E005    | ACTolentino  | 1989-02-20 | F      | Maligaya | 30000.00 | D002    |
| E006    | ANVillasoto  | 1999-01-05 | M      | CLSU     | 15000.00 | D004    |
| E007    | JPPalada     | 1997-01-10 | M      | Munoz    | 21000.00 | D001    |
| E008    | NTNicodemus  | 1995-04-15 | F      | Maligaya | 22000.00 | D003    |
+---------+--------------+------------+--------+----------+----------+---------+

我要在DNumber中显示所有重复值

  +---------+--------------+------------+--------+----------+----------+---------+
| ENumber | EmpName      | Birthdate  | Gender | Address  | Salary   | DNumber |
+---------+--------------+------------+--------+----------+----------+---------+
| E004    | APGamilla    | 1991-10-15 | F      | Maligaya | 25000.00 | D001    |
| E007    | JPPalada     | 1997-01-10 | M      | Munoz    | 21000.00 | D001    |
| E003    | ALedesma     | 1988-05-25 | M      | CLSU     | 21000.00 | D002    |
| E005    | ACTolentino  | 1989-02-20 | F      | Maligaya | 30000.00 | D002    |
| E002    | EAVillanueva | 1988-04-20 | F      | Munoz    | 23000.00 | D003    |
| E008    | NTNicodemus  | 1995-04-15 | F      | Maligaya | 22000.00 | D003    |

Answer 1

使用分组依据并具有
来显示mysql中所有重复的值

有多种方法可以执行此操作，但是，如果要使用group by和having，则可以将表与标识重复项的聚合子查询联接起来，如下所示：< / p>

select t.*
from mytable t
inner join (
    select dnumber
    from mytable
    group by dnumber
    having count(*) > 1
) x on x.dnumber = t.dnumber
order by t.dnumber, t.enumber

如何显示所有重复值

1 个答案: