摘要: --group by与case when配合使用:select A,count(case when not B is null then A end) as Cnt from TBL group by A--执行select A,case when not B is null then A end 阅读全文
posted @ 2017-11-08 09:51 剑诀浮云 阅读(8668) 评论(0) 推荐(1) 编辑