如下表: 表名:Test ID RowID Col1 Col2 1 1 A A 2 1 B A 3 1 A B 4 1 C B 1,查找表中字段重复的只查找一次 select distinct Col1 from Test ; select Col1 from Test where ID in(select min(ID) from Test group by Col1 ); 结果为: A B C 2,统计并查询该字段出现的数量 SELECT Col1,COUNT(Col1) FROM Tes
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 by peopleId having count(peopleId) > 1) 例二: select * from testtable where numeber in (select number from people group by number havi
delete from proj_info where newcode in (select newcode from proj_info group by newcode having count(newcode) > 1) and NID not in (select min(nid) from proj_info group by newcode having count(newcode)>1)
SELECT * FROM tab_init WHERE id IN ( --根据Data分类获取数据最小ID列表 select max(id) from tab_init group by a,b ) 先找出重复数据的 最大的Id ( group by 后面可跟多列, 根据规则找到重复数据), 取出 id 最大或最小的 Id, 然后使用 in查询,就可以得到不重复的数据
--1.建立表:Coursecreate table Course( ID int identity(1,1),--ID Student varchar(20) ,--学生 Sub varchar(20) ,--课程) --2.插入数据INSERT INTO CourseVALUES ('张三','语文'),('李四','语文' ),('王五','语文' ) INSERT INTO CourseVALUES ('张三','语文'),('李四','英语' ),('王五','数学' ) INSERT
最近发布的脚本,有那种防止重复插入数据(包括存在时更新,不存在是插入的处理,判断的方向可能与下面的示例相反) 使用类似下面的 SQL declare @id int, @value int if not exists( select * from tb where id = @id ) insert tb values( @id, @value ); --else -- update tb set value = @value where id = @id; 或者是使用这种单句的 declar
sql代码如下: 统计重复的数据 select MingCheng from tabShouFeiGongShi group by MingCheng having count(MingCheng) >= 2 select * from (select *from tabShouFeiGongShiwhere MingCheng in (select MingCheng from tabShouFeiGongShi group by MingCheng having count(MingChe
删除重复的数据,在平时的工作中还是会和碰到的,感觉挺有用,从网上摘录的,记在这里,以备需要时查阅 --方法一,IN方式,适合2000/2005/2008,6728 毫秒 DELETE [student_L] WHERE id NOT IN ( SELECT MAX(id)--min(id) FROM [student_L] GROUP BY [stuid], [stuname], [Birthday], [AreaOrganID] ) /* SQL Server 分析和编译时间: CPU 时间=
select * from (SELECT titleid,count(titleid) c FROM [DragonGuoShi].[dbo].[ArticleInfo] group by titleid,[CategoryCode] having count(titleid)>1)as t order by c delete [DragonGuoShi].[dbo].[ArticleInfo] where ID not in ( SELECT max(ID) c FROM [DragonGu
1.表结构与数据: CREATE TABLE tablezzl( id int, name ) ); 2.查询出重复的数据: 3.查询出要保留的重复数据: 4.最终的SQL: DELETE FROM tablezzl ) ) a) ) ) b) 5.补充 : 其中这样写mysql中不能如下这样写: DELETE FROM tablezzl ) ) 会报错:You can't specify target table 'tablezzl' for update in FROM clause,不能在
--首先将不是重复的数据提取出来,保存到一个临时表中 select distinct * into #temp from JX_Score --然后删除原来的表 delete from JX_Score --最后往里面插入临时表的数据 insert into jx_score select * from #temp
由于一次操作失误,给表中插入了多条重复的数据,所以就需要删除重复的数据只保留一条,一时想不到好方法,各种查资料,终于找到了,特意写到这里,方便以后自己用~ 查询: select A.n_PatentID,A.s_OtherFileName,A.s_FileName FROM TB_OtherFiles A, (SELECT n_PatentID,s_OtherFileName,s_FileName FROM TB_OtherFiles ) ) AS B order by n_PatentID 删
我们一般情况下通过分组函数group by来查询重复的列 ) R 但是查询出的结果不能显示该表的其他列 想要查询一张表中有多个列重复的数据且也要显示该表的其他列 SELECT M.* FROM [dbo].[Table] M, (SELECT * ) R ) M1 where M.[column1]=M1.[column1] AND M.[column2]=M1.[column2]