#内连接
select * from auth_user u inner join auth_group g on u.id = g.id;
#左连接
select * from auth_user a left join auth_group b on a.id = b.id;
#右连接
select * from auth_user a right join auth_group b on a.id = b.id;
#左链接-内连接
select * from auth_user a left join auth_group b on a.id = b.id where b.id is null;
#右连接-内连接
select * from auth_user a right join auth_group b on a.id = b.id where b.id is null;
#mysql外连接不让使用full join 或者full outer join
如对本文有疑问, 点击进行留言回复!!
一步步教你用Prometheus搭建实时监控系统系列(一)——上帝之火,普罗米修斯的崛起
网友评论