如何獲取每個家長的子類別的物品計數？

Question

這與以下職位：

The function that retrieves the item counts for each folder (category) is: 

ALTER FUNCTION [dbo].[GetFolderReceiptCount] 
(
    -- Add the parameters for the function here 
    @FolderID bigint 
) 
RETURNS int 
AS 
BEGIN 

    DECLARE @Return int 

    SET @Return = 0 

    SELECT 
     --H.ReceiptFolderID, 
     @Return = COUNT(H.ReceiptFolderID) 
    FROM 
     tbl_ReceiptFolderLnk H 
     JOIN tbl_Receipt D ON H.ReceiptID = D.ReceiptID 
    WHERE ReceiptFolderID=@FolderID 
    GROUP BY 
     H.ReceiptFolderID 

    -- Return the result of the function 
    RETURN @Return  

END 

這怎麼可能改變返回計數爲每個父？

Answer 1

你應該改變函數返回一個表變量，或使用存儲過程，這樣你可以得到一個數據集

的SQL語句應該與此類似：

SELECT 
    H.ReceiptFolderID, COUNT(H.ReceiptFolderID) 
FROM 
    tbl_ReceiptFolderLnk H 
    JOIN tbl_Receipt D ON H.ReceiptID = D.ReceiptID 
WHERE ReceiptFolderID=@FolderID 
GROUP BY 
    H.ReceiptFolderID