求sql语句优化

[水桶IIII]

select invent.cDepotId,invent.cprodid 
,case when in_iQuantity is null then 0 else in_iQuantity end in_iQuantity 
,case when in_iSuCentiare is null then 0 else in_iSuCentiare end in_iSuCentiare 
,case when in_iSuAmt is null then 0 else in_iSuAmt end in_iSuAmt 
,case when ou_iQuanTity is null then 0 else ou_iQuanTity end ou_iQuanTity 
,case when ou_iSuCentiare is null then 0 else ou_iSuCentiare end ou_iSuCentiare 
from  (
select depot.cDepotId,cDepotName,invent.cClassId,cProdid,cProdName,iCentiare,cSpecif,cUnit 
from invent FULL OUTER JOIN depot on invent.cProdid<>depot.cDepotId 
)invent left join (
select cDepotId,paperlog.cProdId,sum(iQuanTity)in_iQuanTity,sum(iSuCentiare)in_iSuCentiare,sum(iSuAmt)in_iSuAmt   
from paperlog,papClass  
where paperlog.cPapcType=papClass.cPapcType and paperlog.iyear=2012 and paperlog.imonth=7 and papClass.cPapcName='入库' 
group by cDepotId,cProdId) inPaperlog on invent.cProdId=inPaperlog.cProdid and invent.cDepotId=inPaperlog.cDepotId 
left join (
select cDepotId,paperlog.cProdId,sum(iQuanTity)ou_iQuanTity,sum(iSuCentiare)ou_iSuCentiare 
from paperlog,papClass  
where paperlog.cPapcType=papClass.cPapcType and paperlog.iyear=2012 and paperlog.imonth=7 and papClass.cPapcName='出库' 
group by cDepotId,cProdId
)ouPaperlog on invent.cProdId=ouPaperlog.cProdId and invent.cDepotId=ouPaperlog.cDepotId  
where in_iQuantity<>0 or in_iSuCentiare<>0 or in_iSuAmt<>0 or ou_iQuanTity<>0 or ou_iSuCentiare<>0 
order by invent.cprodid,invent.cDepotId

这个语句，执行不了，Sql服务器好像死循环了
如果把
where in_iQuantity<>0 or in_iSuCentiare<>0 or in_iSuAmt<>0 or ou_iQuanTity<>0 or ou_iSuCentiare<>0
这句给删除了，查询出来的记录也才80000多条
为什么会这样呢？

求师兄师姐给指点一下，谢谢！

[--小F--]

case when in_iQuantity is null then 0 else in_iQuantity

这样的可以换成ISNULL(in_iQuantity ,0)

另外你的子查询也太多了 都是嵌套。

[开着拖拉机泡妞]

建议是使用临时表处理掉一部分子查询

[天-笑]

--try
select invent.cDepotId,invent.cprodid 
		,case when in_iQuantity is null then 0 else in_iQuantity end in_iQuantity 
		,case when in_iSuCentiare is null then 0 else in_iSuCentiare end in_iSuCentiare 
		,case when in_iSuAmt is null then 0 else in_iSuAmt end in_iSuAmt 
		,case when ou_iQuanTity is null then 0 else ou_iQuanTity end ou_iQuanTity 
		,case when ou_iSuCentiare is null then 0 else ou_iSuCentiare end ou_iSuCentiare 
from  (
	select depot.cDepotId,cDepotName,invent.cClassId,cProdid,cProdName,iCentiare,cSpecif,cUnit 
	from invent FULL OUTER JOIN depot on invent.cProdid<>depot.cDepotId 
)invent 
left join (
	select cDepotId,paperlog.cProdId,
			sum(case when papClass.cPapcName = '入库'  then iQuanTity else null end) as in_iQuanTity,
			sum(case when papClass.cPapcName = '入库'  then iSuCentiare else null end) as iSuCentiare,
			sum(case when papClass.cPapcName = '入库'  then iSuAmt else null end) as iSuAmt,
			sum(case when papClass.cPapcName = '出库'  then iQuanTity else null end) as ou_iQuanTity,
			sum(case when papClass.cPapcName = '出库'  then iSuCentiare else null end) as ou_iSuCentiare
	from paperlog,papClass  
	where paperlog.cPapcType=papClass.cPapcType and paperlog.iyear=2012 and paperlog.imonth=7  
	group by cDepotId,cProdId
) Paperlog
on invent.cProdId=Paperlog.cProdid and invent.cDepotId=Paperlog.cDepotId 
where in_iQuantity<>0 or in_iSuCentiare<>0 or in_iSuAmt<>0 or ou_iQuanTity<>0 or ou_iSuCentiare<>0 
order by invent.cprodid,invent.cDepotId

[天-笑]

--try2
select invent.cDepotId,invent.cprodid 
		,isnull(in_iQuantity,0) as in_iQuantity
		,isnull(in_iSuCentiare,0) as in_iSuCentiare
		,isnull(in_iSuAmt,0) as in_iSuAmt
		,isnull(ou_iQuanTity,0) as ou_iQuanTity
		,isnull(ou_iSuCentiare,0) as ou_iSuCentiare
from  (
	/*这个子查询能再优化下吗？*/
	select depot.cDepotId,cDepotName,invent.cClassId,cProdid,cProdName,iCentiare,cSpecif,cUnit 
	from invent FULL OUTER JOIN depot on invent.cProdid<>depot.cDepotId 
)invent 
left join (
	select cDepotId,paperlog.cProdId,
			sum(case when papClass.cPapcName = '入库'  then iQuanTity else null end) as in_iQuanTity,
			sum(case when papClass.cPapcName = '入库'  then iSuCentiare else null end) as iSuCentiare,
			sum(case when papClass.cPapcName = '入库'  then iSuAmt else null end) as iSuAmt,
			sum(case when papClass.cPapcName = '出库'  then iQuanTity else null end) as ou_iQuanTity,
			sum(case when papClass.cPapcName = '出库'  then iSuCentiare else null end) as ou_iSuCentiare
	from paperlog,papClass  
	where paperlog.cPapcType=papClass.cPapcType and paperlog.iyear=2012 and paperlog.imonth=7  
	group by cDepotId,cProdId
) Paperlog
on invent.cProdId=Paperlog.cProdid and invent.cDepotId=Paperlog.cDepotId 
where in_iQuantity<>0 or in_iSuCentiare<>0 or in_iSuAmt<>0 or ou_iQuanTity<>0 or ou_iSuCentiare<>0 
order by invent.cprodid,invent.cDepotId

[白天的猫头鹰]

写的太复杂了，多个表关联，里面还存在group by，这样必然会慢，而且还很多<>

建议做以下修改
第一种方式
1、使用存储过程或sql自定义函数，
2、分拆以上的sql语句，单独三个临时表，并给临时表创建索引
临时表一
select depot.cDepotId,cDepotName,invent.cClassId,cProdid,cProdName,iCentiare,cSpecif,cUnit
from invent FULL OUTER JOIN depot on invent.cProdid<>depot.cDepotId

临时表二
select cDepotId,paperlog.cProdId,sum(iQuanTity)in_iQuanTity,sum(iSuCentiare)in_iSuCentiare,sum(iSuAmt)in_iSuAmt
from paperlog,papClass
where paperlog.cPapcType=papClass.cPapcType and paperlog.iyear=2012 and paperlog.imonth=7 and papClass.cPapcName='入库'
group by cDepotId,cProdId) inPaperlog on invent.cProdId=inPaperlog.cProdid and invent.cDepotId=inPaperlog.cDepotId

临时表三
select cDepotId,paperlog.cProdId,sum(iQuanTity)ou_iQuanTity,sum(iSuCentiare)ou_iSuCentiare
from paperlog,papClass
where paperlog.cPapcType=papClass.cPapcType and paperlog.iyear=2012 and paperlog.imonth=7 and papClass.cPapcName='出库'
group by cDepotId,cProdId

然后再进行表关联

[白天的猫头鹰]

[Quote=引用楼主 的回复:]
SQL code

select invent.cDepotId,invent.cprodid
,case when in_iQuantity is null then 0 else in_iQuantity end in_iQuantity
,case when in_iSuCentiare is null then 0 else in_iSuCentiare end in_iSuCent……
[/Quote]

在联表查询时候，进行group by效率上肯定是很低的，还不如单独外面先进行group by 再进行联表查询操作

另外这里也可以使用CTE 操作，这样就避免使用临时表