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mysql去重计数_MySQL
- WBOYOriginal
- 2016-06-01 13:17:532313browse
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要求：
有两个表ttest1、ttest2，结构如下，求 localname ，用户数
ttest1：地区码、用户id
ttest2 ：地区名、地区码
sql：SELECT localname , COUNT( DISTINCT uid )FROM ttest1,ttest2WHERE ttest1.localid = ttest2.localidGROUP BY localname
结果：
缺陷：对于地区d，没有显示用户为0大家有什么好的方法，欢迎回复 bitsCN.com
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