摘要: 1、DISTINCT SELECT DISTINCT 列名称 FROM 表名称 2、!= 和 not select * from emp where job != 'clerk'; select * from emp where not job = 'clerk'; 3、between ... an 阅读全文
posted @ 2018-07-17 16:27 小二柯 阅读(155) 评论(0) 推荐(0)