㈠ sql 查询语句 数据库 过滤重复记录
使用分析函数抄row_number(大部分袭数据库的新颁布都支持),对数据按你需要的重复字段进行编号,然后只取编号值为1的记录。
类似于:
select d.*
from (
-- 按mobile, area, address, post_code对记录进行分组排序,并且按accept_name升序排
select row_number() over (group by mobile, area, address, post_code order by accept_name) as row_idx, s.*
from dt_orders s
) d
where d.row_idx = 1
㈡ sql语句查询过滤重复数据
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
复制代码代码如下:
select * from people
where peopleId in (select peopleId from people group by peopleId having count
(peopleId) > 1)
2、删除表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断,只留有rowid最小的记录
复制代码代码如下:
delete from people
where peopleId in (select peopleId from people group by peopleId having count
(peopleId) > 1)
and rowid not in (select min(rowid) from people group by peopleId having count(peopleId
)>1)
㈢ sql查询去掉重复记录
1、打抄开要去掉重复数据的数据库,这里新建一张含有重复数据的user表做示例,如下图所示:
㈣ 用SQL语句怎么过滤重复数据
有一半是添加表的,因为我没有你的结果集,所以拼了个表变量做为结果集
,重点在后半部分,处理逻辑是按你的想写的,前提是如果我没有理解错的话
这个方法的结果集返回的是每一年的数据,年数递增的,行数以有多少个城市为准,不过我感觉你要这样的结果集没有什么意义
declare @tab table(name nvarchar(20), both int)
declare @tabtmp table(name nvarchar(20), both int)
declare @tabname table(name nvarchar(20))
declare @name nvarchar(20)
declare @both int
insert into @tab
select N'上海',1996
union
select N'上海',1997
union
select N'北京',1996
union
select N'北京', 1997
insert into @tabname
select distinct name from @tab
select top 1 @name=name from @tab order by name asc
select @both=MIN(both) from @tab
while(@name is not null)
begin
insert into @tabtmp
select @name,@both
update @tab set name='' where name=@name
set @name=null
select top 1 @name =name from @tab where name<>'' order by name asc
select top 1 @both=both from @tab where both>@both order by both asc
end
select * from @tabtmp
㈤ SQL如何过滤特定字段重复
你是要每个单位一条记录吗?
select 单位=a.dw,MAX(单位属性=c.dwsx),MAX(商品编码=a.bh),MAX(品规=a.pm),MAX(分类=b.lm1,MAX(电话=c.dh)
FROM gjht A
LEFT JOIN SPML B ON A.BH=B.BH
LEFT JOIN KHML C ON A.DW=C.DW where b.lm1 like '食品%'
GROUP BY 单位=a.dw
㈥ sql 查询去除重复行
order by (select 1)与order by 1一样按第一列排序,按照查询的结果集第一列排序
㈦ sql 如何过滤重复记录
SQL过滤重复记录有两种办法:
通过SQL结构化查询语言来实现,在Select后面加上关键字DISTINCT,意思就是查询行无重复,注意DISTINCT关键字是针对行,不是某一列,如果想得到某一列不重复记录,那就SELECT DISTINCT后面只放一个字段。
通过存储过程,过滤重复记录,存储过程逐条查询,比对之前的记录,如果有重复就跳到下一条,如果不重复游标继续。
㈧ sql查询语句过滤重复数据。
SELECT Id,SiteId,InsertTime,IP,Referrer,Url
FROM
(
SELECT ROW_NUMBER()OVER(PARTITION BY IP ORDER BY Id DESC) number,
Id,SiteId,InsertTime,IP,Referrer,Url
From YourTable
)T
where number = 1
拿走不谢
㈨ sql 如何过滤重复记录
问题背景
在一个多表查询的sql中正常情况下产生的数据都是唯一的,但因为数据库中存在错误(某张表中存在相同的外键ID)导致我这边查询出来的数据就会有重复的问题
下面结果集中UserID:15834存在多个
参考:
MSDN: OVER 子句 (Transact-SQL)
stackoverflow sql query distinct with Row_Number
SQL Trick: row_number() is to SELECT what dense_rank() is to SELECT DISTINCT
㈩ SQL查询中如何剔除重复
1,存在两条完全相同的纪录
这是最简单的一种情况,用关键字distinct就可以去掉
example: select distinct * from table(表名) where (条件)
2,存在部分字段相同的纪录(有主键id即唯一键)
如果是这种情况的话用distinct是过滤不了的,这就要用到主键id的唯一性特点及group by分组
example:
select * from table where id in (select max(id) from table group by [去除重复的字段名列表,....])
3,没有唯一键ID
example:
select identity(int1,1) as id,* into newtable(临时表) from table
select * from newtable where id in (select max(id) from newtable group by [去除重复的字段名列表,....])
drop table newtable
(10)sql查找过滤重复代码扩展阅读
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 people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
2、删除表中多余的重复记录,重复记录是根据单个字段(peopleId)来判断,只留有rowid最小的记录
delete from people
where peopleId in (select peopleId from people group by peopleId having count(peopleId) > 1)
and rowid not in (select min(rowid) from people group by peopleId having count(peopleId )>1)
3、查找表中多余的重复记录(多个字段)
select * from vitae a
where (a.peopleId,a.seq) in (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)