https://blog.csdn.net/qazx123q/article/details/90638581
比如表A中
字段1 字段2
1 a
2 a
1 b
1 b
2 a
用sql語句實現查詢,查詢出
1 a
1 b
-
select distinct x.字段一,x.字段二
-
from a as x,a as y
-
where x.字段一=y.字段一 and x.字段二!=y.字段二