按COUNT（*）过滤？

Question

是否可以对结果进行分组，然后根据组中有多少行进行过滤？

事情是这样的：

SELECT * FROM mytable WHERE COUNT(*) > 1 GROUP BY name 

Answer 1

你要使用具有对聚合函数进行筛选。

SELECT name, COUNT(*) 
    FROM mytable 
    GROUP BY name 
    HAVING COUNT(*) > 1 

Answer 2

您需要使用HAVING

SELECT * FROM mytable GROUP BY name HAVING COUNT(*) > 1 

虽然SELECT *不会使当你分组太大的意义。我认为它只是一个在你的查询为例

Answer 3

用途：

SELECT * FROM mytable GROUP BY name having COUNT(*) > 1 

Answer 4

你想要一个HAVING子句。

SELECT * 
FROM mytable 
GROUP BY name 
HAVING COUNT(*) > 1