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sql语句找出重复数据

查询重复数据,方法如下:select * from [表A] where id in (select id from [表A] group by id having count(id) >1 )

如果后面地址都是一样,那么还可以这样 select * from 表A where name in (select distinct name from 表B ) 或者用Group by 也行

select count(字段) from tableselect count(distinct 字段) from table不相等就说明有重复字段了然后再查重复值select count(字段) as total,字段 from table where total > 1 group by 字段

select id, name, memo from A where id in (select id from A group by id having count(1) >= 2) 以上回答你满意么?

select * from tablename where 重复字段1 in (select 重复字段1 from tablename group by 重复字段1,重复字段2 having count(*)>1).SQL重复记录查询方法: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 *

方法如下: select * from 你的表名 a where id=(select min(id) from 你的表名 whereitem_id=a.item_id) 在查询之前先把数据库表中的第一行复制到sid里在去,然后让sid和下面的每一行进行比较 取所有相同的行的最小的一下,也可以取最大

假设该表id作为pk,只保留一条shopname不重复数据 delete from shop where id not in(select min(id) from shop group by shopname) 效率不是很高,但是通用性比较强

1.查出姓名,科目,分数相同的记录select * from A as out where exists(select * from (select a1,a2,a3 from A group by a1,a2,a3 having count(*) > 1) as bwhere a1 = out.a1 and a2 = out.a2 and a3 = out.a3)2. 删出姓名,科目,分数相同的记录(这里

select distinct username from [user]delete [user] where username=相同值insert [user] select username from temp1drop table temp1

insert into tbquotationlist (c1,c2,c3,c4) select c1,'修改后的数据',c3,c4 from tbquotationlist where id=3 如果c2字段类型为数字型,则把单引号去掉,内容改为数字即可.但修改写的数据要注意不要超出c2字段的长度

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