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使用sql sErvEr 怎么查重复数据

select id, name, memo from A where id in (select id from A group by id having count(1) >= 2)

select * from 表 where 字段 in( select 字段 from 表 group by 字段 having count(1)>1)

按照内容进行分组,查询记录数是否大于1 select * from (select datatime,code,name,count(*) as nrow from table1 group by datatime,code,name) tawhere ta.nrow>1

1.查询出重复记录 select 重复记录字段 form 数据表 group by houseno having count(重复记录字段)>1 2.重复记录只显示一条ID值最小或最大的记录 select id,* from 数据表 where houseno (select 重复记录字段 form 数据表 group by 重复记录 ...

select id,name,age from 表 group by id,name,age having count(1)>=2

select * from stuinfo where stuid in ( select stuid from stuinfo group by stuid having(count(*))>1 ) 或者 select stuid,stuname from stuinfo group by stuid,stuname having(count(*))>1 参见http://kb.cnblogs.com/page/94862/

可用group by……having来实现。 可做如下测试: 1、创建表插入数据: create table test(id int,name varchar(10))insert into test values (1,'张三')insert into test values (2,'李四')insert into test values (3,'张三')insert into test va...

那你就取提交时间最新的那个就行了呗 select * from tb a where not exists(select * from tb where submitter = a.submitter and subtime > a.subtime)

关键字Distinct 去除重复,如下列SQL,去除Test相同的记录; select distinct Test from Table 如果是要删除表中存在的重复记录,那就逻辑处理,如下: select Test from Table group by Test having count(test)>1 先查询存在重复的数据,后面...

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