MySQL的join使用

#內連接
select * from auth_user u inner join auth_group g on u.id = g.id;

#左連接
select * from auth_user a left join auth_group b on a.id = b.id;

#右連接
select * from auth_user a right join auth_group b on a.id = b.id;

#左鏈接-內連接
select * from auth_user a left join auth_group b on a.id = b.id where b.id is null;

#右連接-內連接
select * from auth_user a right join auth_group b on a.id = b.id where b.id is null;

#MySQL外連接不讓使用full join 或者full outer join