sql-server-2005 - 根据条件从不同的表中计算 SUM

Question

我有 4 个 SQL Server 2005 表：MainTable、Info、Repairs、Maintenance

MainTable 表：

MainID, PlateNo
1, A123
2, D222

信息表：

InfoID, MainID, Location
1, 1, California
2, 2, Ohio

维修表：

RepairID, MainID, Cost, InvoiceNo, InvoiceDate
1, 1, 250, 3423523, 12/10/2010
2, 1, 340, 5634534, 08/11/2010
3, 2, 125, 9258143, 10/02/2010

保养表：

MaintenanceID, MainID, Cost, InvoiceNo, InvoiceDate
1, 1, 223, 9694534, 07/03/2009
2, 2, 830, 4259943, 01/02/2011

所有表都通过 MainTable 中的 MainID 链接。

我想从每个 PlateNo 的信息表中获取给定“位置”的两个日期（InvoiceDate）之间的维修总和（成本），维护总和（成本）。

Answer 1

我会使用派生表来处理这个查询。您可以轻松地使用公用表表达式。

Select Main.MainId,
       Main.PlateNo,
       Info.Location,
       MaintenanceCosts.MaintenanceCost,
       RepairCosts.RepairCost
From   Main
       Inner Join Info
         On Main.MainId = Info.MainId
       Left Join (
         Select MainId, Sum(Cost) As MaintenanceCost
         From   Maintenance
         Where  InvoiceDate >= @StartDate
                And InvoiceDate < @EndDate
         Group By MainId
         ) As MaintenanceCosts
         On Main.MainId = MaintenanceCosts.MainId
       Left Join (
         Select MainId, Sum(Cost) As RepairCost
         From   Repairs
         Where  InvoiceDate >= @StartDate
                And InvoiceDate < @EndDate
         Group By MainId
         ) As RepairCosts
         On Main.MainId = RepairCosts.MainId
Where  Info.Location = @Location 

Answer 2

尝试这个

select 

isnull(sum(a.[ Cost]) + sum(b.[ Cost]),0) cost,
a.[ MainID],a.[ InvoiceDate]

from 

[maintanen] a inner join 
[repairs] b 

on a.[ MainID]=b.[ MainID]


group by a.[ MainID],a.[ InvoiceDate]

结合位置