sql之left join、right join、inner join的区别
摘要:
转载自 https://www.cnblogs.com/pcjim/articles/799302.html sql之left join、right join、inner join的区别 left join(左联接) 返回包括左表中的所有记录和右表中联结字段相等的记录 right join(右联接) 阅读全文
posted @ 2018-08-16 09:59 wait_for_you 阅读(195) 评论(0) 推荐(0) 编辑