在数据库中某表中,存在着些相同的记录,如何能用SQL语句,删除掉重复的呢1、查找表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断select * from peoplewhere peopleId in (select peopleId from people group ...
方法一: select from tablename where id in select id from tablename group by id having count id gt 方法二: select DISTINCT t. from select from Goods g t ...
2017-12-25 16:50 0 955 推荐指数:
在数据库中某表中,存在着些相同的记录,如何能用SQL语句,删除掉重复的呢1、查找表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断select * from peoplewhere peopleId in (select peopleId from people group ...
select user_id from dt_orders where datatype=10 and status=3 group by user_id having count(*)>1 ...
返回operation表中time列的唯一值 语句1 select time from operation group by time having count(time) > 1 语句2 select distinct time from operation; ...
select * from (SELECT titleid,count(titleid) c FROM [DragonGuoShi].[dbo].[ArticleInfo] group by tit ...
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1.查询单列重复: 2.查询多列重复 ...
1.查询单列重复(table:表名,name 字段名): select * from table where name in (select name from table group by name having count(name) > 1) 2.查询多列重复(table:表名 ...
去掉重复数据的方法: 第一种:distinct 根据单个字段去重,能精确去重; 作用在多个字段时,只有当这几个字段的完全相同时,才能去重; 关键字distinct只能放在SQL语句中的第一个,才会起作用 上图举例说明:图中student_name 为 test ...