MYSQL 处理重复数据 技术教程文章
Mysql 查询不重复数据【代码】
用户表 app表 用户记录表 现在要想查出用户点击的记录的列表，并且按照用户，时间排序，去掉重复的数据 select distinct a.* from (select n.name,u.phone,n.startmoney,n.endmoney,n.type from loan_record r inner join loan_user u on u.id=r.uid inner join loan_name n on n.id=r.appidwhere r.uid in (select distinct uid from loan_record order by createdate desc) order by u.phone,r.createdate desc) as aw...
mysql删除重复数据【代码】
mysql删除表中重复数据,mysql中是不能直接删除查询出来的记录的,需要使用一个临时表来解决,方式如下:delete from student where stId in(select stId from (select min(stId) stId from student group by stNo having count(stNo) >1) temp_user )如果有多条重复语句,那么重复执行以上语句即可,直到没有执行结果为止。
mysql查询重复数据【代码】【图】
表全部数据 ------------------- 1 查询people_no重复的记录select * from people where people_no in (select people_no from people group by people_no having count(people_no) > 1); ---------------------- 2 查询people_no重复的记录 ，排除最小id，如果删除改为delete fromselect * from people where people_no in (select people_no from people group by people_no having count(people_no) > 1) and id ...