使用FOR XML PATH將計數添加到根元素

Question

我有一個Sql語句，它返回根元素是產品的產品的xml。我怎樣才能將count屬性添加到根元素。

我的SQL是：

SELECT 
id AS 'product_id', 
name AS 'product_name' 
FROM product 
WHERE status = 1 AND ...... 
ORDER BY productid 
FOR XML PATH('product'), ROOT('products') 

結果是

<products> 
    <product> 
    . 
    . 
    </product> 
</products> 

我想改變結果

<products count="100"> 
    <product> 
    . 
    . 
    </product> 
</products> 

Answer 1

SELECT 
COUNT(*) AS '@count', 
(
    SELECT * 
    FROM product c1 FOR XML PATH('product'), TYPE 
) 
FROM product ct FOR XML PATH('products') 

最簡單的方法來過濾被添加條件查詢和子查詢：

SELECT 
COUNT(*) AS '@count', 
(
    SELECT * 
    FROM product c1 
    WHERE c1.status = 1 AND ...... 
    FOR XML PATH('product'), TYPE 
) 
FROM product ct 
WHERE ct.status = 1 AND ...... 
FOR XML PATH('products') 

或者使用臨時表：

SELECT * 
INTO #Temp 
FROM product c1 
WHERE c1.status = 1 AND ...... 


SELECT 
COUNT(*) AS '@count', 
(
    SELECT * 
    FROM #Temp c1 
    FOR XML PATH('product'), TYPE 
) 
FROM #Temp ct 
FOR XML PATH('products') 

你只需添加數= 100或你想利用XML格式的實際計數它應該出現在數