摘要: --select select * from student; --all 查询所有 select all sex from student; --distinct 过滤重复 select distinct sex from student; --count 统计 select count(*) f... 阅读全文
posted @ 2015-11-27 17:15 handsomecui 阅读(617) 评论(0) 推荐(0) 编辑