Question

我正在摆弄XML AUTO和XML RAW以了解它们的行为方式。测试数据库为AdventureWorks2012。

SELECT TOP 20  Cust.CustomerID AS C1,
        Cust.TerritoryID,
        OrderHeader.CustomerID AS C2,
        OrderHeader.SalesOrderID,
        OrderHeader.Status

FROM Sales.Customer Cust
INNER JOIN Sales.SalesOrderHeader OrderHeader
ON Cust.CustomerID = OrderHeader.CustomerID
FOR XML RAW('MyRow'), ELEMENTS

XML RAW的简单性只是将每个元素放在同一级别

<MyRow>
<C1>29825</C1>
<TerritoryID>5</TerritoryID>
<C2>29825</C2>
<SalesOrderID>43659</SalesOrderID>
<Status>5</Status>

对于XML AUTO

SELECT TOP 20  Cust.CustomerID,
        Cust.TerritoryID,
        OrderHeader.CustomerID,
        OrderHeader.SalesOrderID,
        OrderHeader.Status
FROM Sales.Customer Cust
INNER JOIN Sales.SalesOrderHeader OrderHeader
ON Cust.CustomerID = OrderHeader.CustomerID
FOR XML AUTO, ELEMENTS

我有

<Cust>
<CustomerID>29825</CustomerID>
<TerritoryID>5</TerritoryID>
<OrderHeader>
    <CustomerID>29825</CustomerID>
    <SalesOrderID>43659</SalesOrderID>
    <Status>5</Status>
</OrderHeader>
</Cust>

XML AUTO决定将所有Cust标记分组。如何得出这样的结论：Cust以某种方式包含在＆＃34;更高层次＆＃34;比OrderHeader。为什么它决定将所有OrderHeader列列在OrderHeader标记下，而Cust则不一样？在执行之前我认为它会是

<Cust>
    <CustomerID>29825</CustomerID>
    <TerritoryID>5</TerritoryID>
</Cust>
<OrderHeader>
    <CustomerID>29825</CustomerID>
    <SalesOrderID>43659</SalesOrderID>
    <Status>5</Status>
</OrderHeader>

更新

这是一种预感，但我开始认为SQL Server会将首先提到的列的表作为外部标记，

例如，

SELECT TOP 20  OrderHeader.CustomerID,,
               Cust.CustomerID,
               Cust.TerritoryID,
               OrderHeader.SalesOrderID,
               OrderHeader.Status

即使我混合了列顺序，它仍然会将OrderHeader的列组合在一起，而Cust是一个子组

<OrderHeader>
<CustomerID>29825</CustomerID>
<SalesOrderID>43659</SalesOrderID>
<Status>5</Status>
<Cust>
<CustomerID>29825</CustomerID>
<TerritoryID>5</TerritoryID>
</Cust>
</OrderHeader>

FOR XML AUTO SQL SERVER的行为

0 个答案: