Group By条件求和MSSQL查询

Question

我有一个表OrderDetails与以下架构:

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|  OrderId  |  CopyCost  |  FullPrice  |  Price  |  PriceType  |
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|  16       |  50        |  100        |  50     |  CopyCost   |
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|  16       |  50        |  100        |  100    |  FullPrice  |
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|  16       |  50        |  100        |  50     |  CopyCost   |
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|  16       |  50        |  100        |  50     |  CopyCost   |
----------------------------------------------------------------

我需要一个查询,将上面的表推测为具有以下模式的新表:

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|  OrderId  |  ItemCount  |  TotalCopyCost  |  TotalFullPrice  |
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|  16       |  4          |  150            |  100             |
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目前我在Order.Id上使用Group By来计算项目数.但我不知道如何有条理地推测CopyCost和FullPrice值.

任何帮助将非常感激.

关心弗雷迪

Answer 1

尝试

SELECT OrderId, 
       COUNT(*) ItemCount,
       SUM(CASE WHEN PriceType = 'CopyCost' THEN Price ELSE 0 END) TotalCopyCost,
       SUM(CASE WHEN PriceType = 'FullPrice' THEN Price ELSE 0 END) TotalFullPrice
  FROM OrderDetails
 GROUP BY OrderId

SQLFiddle

Answer 2

试试这个查询

select 
   orderId, 
   count(*) as cnt, 
   sum(if(pricetype='CopyCost', CopyCost, 0)) as totalCopyCost,
   sum(if(pricetype='FullPrice', FullPrice, 0)) as totalFullPrice
from 
   tbl
group by 
   orderId

SQL小提琴：

| ORDERID | CNT | TOTALCOPYCOST | TOTALFULLPRICE |
--------------------------------------------------
|      16 |   4 |           150 |            100 |