http://bbs.csdn.net/topics/380258986
select name from score group by name
select distinct name from score
连个的效果一样
http://zhidao.baidu.com/link?url=sLocMoGf0qcvuCr_onRLAUEoXXgtkFlaxqRGjMSsL26-evQvXggDun9JaeEkktxNNHM7qnAxE97e8c1uVW8Fg_
我在where 1=1 后面加了 and where 1=1 and goup by 多了and 会报错的
区分
having
group by
order by
where 1=1
distinct
原文：http://www.cnblogs.com/zshboke-2015/p/4966705.html