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我有一个 sql 存储过程，其中我使用一个游标，其中包含来自 select 语句的一组 id，我使用这些 id 使用游标将值逐个遍历以将值放入其他变量并使用这些变量进行 sql 连接。我的问题是当我执行此操作时，我返回了许多表，而我只需要返回一个表。

SET NOCOUNT ON


declare @BSVal as int
declare @GSVal as int

declare @mID as int
declare @qID as int

DECLARE M_Cursor cursor for

select 
ms.MID,ms.QID
from  vM As ms join QS as qs
ON ms.QSID=qs.QIDjoin 
Mar as mar on mar.MarID=qs.MarID
where (ms.Cid='Web')

open M_Cursor

FETCH NEXT FROM M_Cursor 
INTO @mID, @qID


--Get values
WHILE @@FETCH_STATUS = 0
BEGIN
set @BSVal= (select top 1 SCID from vSC where (EnID in 
(select EnID from En where EnName='BAIDU')
and QTID=1 and MID=@mIDand QSID=@qID)order by ITime desc); 
set @GSVal= (select top 1 SCID from vSC where ( EnID in 
(select EnID from En where EnName='GRAPHIC') and QTID=1 
and MID=@mIDand QSID=@QSID) order by ITime desc);




select  * from 

vM m 

join vw5TABLE BNDCG on (m.QSid=BNDCG.QID And BNDCG.Position=1) 
join vw5TABLE GNDCG on (m.QSid=GNDCG.QID And GNDCG.Position=1)

where

BNDCG.SCid=@BSVal
and GNDCG.SCid=@GSVal
and BNDCG.QSID=@ qID
and GNDCG.QSID=@ qID
and m.MID=@mID




FETCH NEXT FROM M_Cursor 
   INTO @MID, @QSID


END
CLOSE M_Cursor;
DEALLOCATE M_Cursor;
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1 回答 1

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该代码将为游标的每次迭代运行一个选择，这使它看起来像“许多表”。听起来您需要将该选择的结果插入游标内的临时表或表变量中，然后在游标完成后，从该临时表中选择一次。我没有详细查看您的代码，但我猜可能不需要光标。

这是使用表变量的粗略示例。

DECLARE @temptable  TABLE (col1 INT, Col2 VARCHAR(3), Col3 INT)


insert into @temptable (col1,col2,col3)
select  (col1,col2,col3) from 
vM m 
join vw5TABLE BNDCG on (m.QSid=BNDCG.QID And BNDCG.Position=1) 
join vw5TABLE GNDCG on (m.QSid=GNDCG.QID And GNDCG.Position=1)
where
BNDCG.SCid=@BSVal
and GNDCG.SCid=@GSVal
and BNDCG.QSID=@ qID
and GNDCG.QSID=@ qID
and m.MID=@mID

....
..

DEALLOCATE M_Cursor;

SELECT Col1,Col2,Col3 FROM @temptable
于 2013-04-04T23:51:29.663 回答