sql+mysql 随机数据读取---进阶问题
比如有一个表 class , 里面的数据是一个花名册, 比如姓名,年龄,性别,籍贯
我现在想得到这么一个随机的结果: 按照籍贯,每个省份随机列出一条记录. 花名册里有的省份都要读取到.
请问这 SQL 语句该怎么写?
------解决方案--------------------
select m.* from (select * from user order by rand()) m group by m.area_id
user是你的表名,area_id是籍贯
问题解决。
如果对你有帮助,麻烦帮我点一下我网站的广告,谢谢。
网址:http://blog.72-web.com

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