在SQL Server 2008/2012的單個SQL語句中返回子記錄

Question

我目前在存儲過程中有以下SQL語句;

SELECT [Id], 
    [Path], 
    [Title], 
    [Description] 
FROM [Configuration].[Pages] p 
WHERE 
    ((p.Id = @Id) OR (@Id IS NULL)) AND 
    ((p.Path = @Path) OR (@Path IS NULL)) 

這使我可以通過頁面的路徑，頁面的ID或沒有任何東西（返回所有）。

我期待重構這個返回相關的子記錄（1到M），而不是返回數據庫中的每個返回的記錄。子記錄的當前SQL如下所示;

SELECT  h.Id, h.Description, h.Title, h.[Content] 
FROM   [Configuration].[HelpItems] h INNER JOIN 
         [Configuration].[PageHelpItems] ph ON h.Id = ph.HelpId 
WHERE  (ph.PageId = @PageId) 

目前，我通過每個父記錄的循環和調用此存儲過程的每一個，我相信這是低效的，我想有與保證孩子的SP的一個或多個SQL語句所有家長都會返回記錄。

Answer 1

所以，你想記錄

;WITH Rec AS (
    SELECT [Id], 
     [Path], 
     [Title], 
     [Description] 
    FROM [Configuration].[Pages] p 
    WHERE 
     ((p.Id = @Id) OR (@Id IS NULL)) AND 
     ((p.Path = @Path) OR (@Path IS NULL)) 
) 
SELECT 'Main' Which, * FROM Rec 
-- plus the children... 
UNION ALL 
SELECT 'Related', h.Id, h.Title, h.Description, h.[Content] 
FROM [Configuration].[HelpItems] h 
INNER JOIN [Configuration].[PageHelpItems] ph ON h.Id = ph.HelpId 
INNER JOIN Rec ON Rec.Id = ph.PageId 

Answer 2

嘗試使用下面的查詢：

SELECT  h.Id, h.Description, h.Title, h.[Content] 
FROM   [Configuration].[HelpItems] h INNER JOIN 
        [Configuration].[PageHelpItems] ph ON h.Id = ph.HelpId 
       INNER JOIN [Configuration].[Pages] p ON ph.PageId = p.Id 
WHERE  
    ((p.Id = @Id) OR (@Id IS NULL)) AND  
    ((p.Path = @Path) OR (@Path IS NULL))