① sqlserver 去掉重復記錄
首先設定表tb_a 唯一關鍵欄位 xh,以及要查詢的重復欄位 mc 則查詢mc重復的sqlserver語句如下
select mc from tb_a where xh not in (select min(xh) xh from tb_a group by mc)
② sql server去重
老生常談,沒有編號的話,你自己使用row_number生成一個編號,然後刪除相應的數據
sqlserver使用row_number去重
你可以看一看裡面的寫法,主要原理,分組生成編號,最後只保留分組中編號為一的一行數據,其餘的數據都刪除掉。
delete[A2]from
(selectrow_number()over(PartitionBybabyname,[公司名稱],[調查結果]
orderbybabyname)askeyId2,*
from[測試])as[A2]
where[A2].keyId2!=1
請試一試,如有疑問,及時溝通!
③ sqlserver怎麼刪除重復數據
1、查找表中多餘的重復記錄,重復記錄是根據單個欄位(peopleId)來判斷
select
* from people
where peopleId in (select peopleId from
people group by peopleId having count(peopleId)
> 1)
2、刪除表中多餘的重復記錄,重復記錄是根據單個欄位(peopleId)來判斷,只留有rowid最小的記錄
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、查找表中多餘的重復記錄(多個欄位)
select * from vitae a
where (a.peopleId,a.seq)
in (select peopleId,seq from vitae group by peopleId,seq having
count(*) > 1)
4、刪除表中多餘的重復記錄(多個欄位),只留有rowid最小的記錄
delete from vitae a
where
(a.peopleId,a.seq) in (select peopleId,seq from vitae group by
peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from
vitae group by peopleId,seq having count(*)>1)
5、查找表中多餘的重復記錄(多個欄位),不包含rowid最小的記錄
select * from vitae a
where
(a.peopleId,a.seq) in (select peopleId,seq from vitae group by
peopleId,seq having count(*) > 1)
and rowid not in (select min(rowid) from
vitae group by peopleId,seq having count(*)>1)
(二)
比方說
在A表中存在一個欄位「name」,
而且不同記錄之間的「name」值有可能會相同,
現在就是需要查詢出在該表中的各記錄之間,「name」值存在重復的項;
Select
Name,Count(*) From A Group By Name Having Count(*) > 1
如果還查性別也相同大則如下:
Select Name,sex,Count(*) From A Group By Name,sex Having
Count(*) > 1
④ SqlServer 去重
用excel畫個草圖唄,原來例子什麼樣,你想得到的什麼樣,這樣方便回答
⑤ sql語句去重distinct方法是什麼
sql語句去重distinct方法是根據name和id兩個欄位來去重的。這種方式Access和SQLServer同時支持,返回的結果為兩行,這說明distinct並非是對xing和ming兩列字元串拼接後再去重的,而是分別作用於了xing和ming列。
sql語句去重distinct特點
distinct語句中select顯示的欄位只能是distinct指定的欄位,其他欄位是不可能出現的,例如假如表A有備注列,如果想獲取distincname,以及對應的備注欄位想直接通過distinct是不可能實現的,但可以通過其他方法實現關於SQLServer將一列的多行內容拼接成一行的問題討論。
distinct這個關鍵字用來過濾掉多餘的重復記錄只保留一條,但往往只用它來返回不重復記錄的條數,而不是用它來返回不重記錄的所有值。其原因是distinct只有用二重循環查詢來解決,而這樣對於一個數據量非常大的站來說,無疑是會直接影響到效率的。
⑥ sqlserver 怎樣將所有的欄位去掉重復的數據
找到最大的rowid即可。
Sql代碼:
alter proc getNotDupData
as
--clear temp table
delete ODS.dbo.Agent
delete from stage.dbo.tmpDup
delete from stage.dbo.tmpRowNo
delete from stage.dbo.tmpMaxRowNo
--create p table
insert into stage.dbo.tmpDup
select distinct AgentLogin,AgentSurName,AgentGivenName from stage.dbo.dAgentPerformanceStat
where AgentSurname is not null and agentlogin like '3%' order by AgentLogin
--add rowNo
insert into tmpRowNo
select *,ROW_NUMBER()over(order by AgentLogin) as rowno from tmpDup
--get max rowno
insert into stage.dbo.tmpMaxRowNo
select max(rowno) as 'rowno' from stage.dbo.tmpRowNo group by AgentLogin having count(*)>1
--remove max rowno
delete from stage.dbo.tmpRowNo where rowno in (select * from stage.dbo.tmpMaxRowNo)
--insert into ods
insert into ODS.dbo.Agent select AgentLogin,AgentSurName,AgentGivenName from stage.dbo.tmpRowNo
⑦ SQLServer去重復查詢,不刪除重復數據
1、要有定位基準,也就是說,你的表必需要有一個不重復的鍵值,如果沒有,請你給這個表加一個欄位,將這個欄位設為自增變數欄位,建議為int類型,比如欄位名可為「編碼」。
2、查重復的數據:
select*from表名where編碼in
(select編碼from表名groupby編碼havingcount(1)>=2)
3、刪除所有有重復的記錄:
deletefrom表名where
編碼in(select編碼from表名groupby編碼havingcount(1)>=2)
4、刪去重復的,只留下重復記錄中編碼最大的一條:
deletefrom表名where
編碼in(select編碼from表名groupby編碼havingcount(1)>=2)
and編碼notin(selectmax(編碼)from表名groupby編碼havingcount(1)>=2)