带有WHERE的DISTINCT子句

Question

如何在WHERE中使用DISTINCT子句？例如:

SELECT * FROM table WHERE DISTINCT email; -- email is a column name

我想从具有不同电子邮件地址的表中选择所有列.

Answer 1

如果您指的是其电子邮件唯一的所有列:

SELECT * FROM table WHERE email in
     (SELECT email FROM table GROUP BY email HAVING COUNT(email)=1);

Answer 2

可能由：

SELECT DISTINCT email,id FROM table where id='2';