SQL選擇最後一次出現的行和計數出現次數

我有一個表OrderSpecs。我需要選擇OrderSpecs中的所有行customer ID，但僅選擇order ID每個訂單的最後一次出現（通過時間戳記）。我還想讓我的查詢計算它爲每個OrderID找到的發生次數。SQL選擇最後一次出現的行和計數出現次數

這裏是我的表（濃縮至僅顯示關鍵信息）：

OrderSpecs選擇按日期和CustomerID最近爲了行時

ID  OrderID CustomerID  CreatedDate     SpecDocument 
1  1   5     01/08/2012 11:00:00   *Amendment1* 
2  1   5     02/08/2012 15:32:41   *Amendment2* 
3  2   31    04/08/2012 16:19:00   *Amendment1* 
4  3   5     05/08/2012 12:10:12   *Amendment1* 
5  4   10    08/08/2012 09:32:56   *Amendment1* 
6  1   5     09/08/2012 11:47:02   *Amendment3*

我的查詢工作正常：

SELECT 
    ID, CustomerID, EstimateNo, OrderYear, OrderNo, ProductionNo, AddedBy,  
    AddedDate, SizeLength, SizeWidth, HomeModelID, HomeTypeID, DrawingNo, 
    CustomerReference, BuildPieces, ProductionPieces, Notes, SpecDocument, OrderID 
FROM 
    OrderSpecs AS o 
WHERE 
    (AddedDate = (SELECT MAX(AddedDate) AS Expr1 
        FROM OrderSpecs AS i 
        WHERE (o.OrderID = OrderID))) 
    AND (CustomerID = @CustomerID)

但是，我無法計算出如何計算一個occourances的數量每個OrderID。

例如，我想我的產出表是這樣的（由CustomerID = 5搜索）：

ID  OrderID  CustomerID  CreatedDate   SpecDocument  Count 
6  1   5    09/08/2012 11:47:02 *Amendment3*  3 
4  3   5    05/08/2012 12:10:12 *Amendment1*  1

來源

2012-08-10 RobHurd

它將有助於瞭解您正在使用的實際**數據庫系統**（以及該RDBMS的哪個版本）。 * SQL *只是*結構查詢語言* - 不是數據庫產品... – 2012-08-10 12:15:17

應與SELECT（未經測試）一個子查詢工作

SELECT 
    ID, CustomerID, EstimateNo, OrderYear, OrderNo, ProductionNo, AddedBy,  
    AddedDate, SizeLength, SizeWidth, HomeModelID, HomeTypeID, DrawingNo, 
    CustomerReference, BuildPieces, ProductionPieces, Notes, SpecDocument, OrderID, 
    (SELECT COUNT(*) FROM OrderSpecs AS os WHERE o.OrderID=os.OrderID) as [Count] 
FROM 
    OrderSpecs AS o 
WHERE 
    (AddedDate = (SELECT MAX(AddedDate) AS Expr1 
        FROM OrderSpecs AS i 
        WHERE (o.OrderID = OrderID))) 
    AND (CustomerID = @CustomerID)

來源

2012-08-10 12:17:47

完美的工作！非常感謝Jonas。 – RobHurd 2012-08-10 13:29:56

SQL選擇最後一次出現的行和計數出現次數

回答

相關問題