mysql去重查询表中数据

1、distinct

select count(distinct CName) from tebleselect count(CName) from (select distinct CName from Course) as tempSELECT  DISTINCT text_zhcn FROM dms_menuconfig  -- 去重查询表中数据select DISTINCT(user_id) from user_info where children_merchant_id='kuaiditong';

2、group by

select count(1) from Course group by CName

文档：mysql去重查询表中数据.note
链接：http://note.youdao.com/noteshare?id=581440d92396bab4de6568d1a69baa58&sub=9B8DAB091CC5490BA5F8FA29557CCD67