摘要: 1.关联 1)连接查询(内关联) inner join ... on 两个表连接查询 select * from students inner join classes 查询能够对应班级的学生以及班级信息 select * from students inner join classes on st 阅读全文
posted @ 2019-07-05 17:54 球接子 阅读(247) 评论(0) 推荐(0)