where group by having
摘要：
普通用法：如找出有sn重复的行select * from t_device where isdel=0 group by sn having count(sn)>1 也有些复杂的场景：找没有逻辑区域的机房：select t_idc.id,t_idc.name from t_idc left join idc_safedomain on t_idc.id=idc_safedomain.idc_... 阅读全文
posted @ 2008-09-11 09:46 Arlen 阅读(521) 评论(0) 推荐(0) 编辑
