Exemplo: Construir elementos irmãos com o modo EXPLÍCITO

Aplica-se a:SQL ServerBase de Dados SQL do AzureAzure SQL Managed InstanceBase de dados SQL no Microsoft Fabric

Assuma que queres construir um XML que forneça informação sobre encomendas de vendas. Neste exemplo, <SalesPerson> e <OrderDetail> elementos são irmãos. Cada Ordem tem um <OrderHeader> elemento, um <SalesPerson> elemento e um ou mais <OrderDetail> elementos.

<OrderHeader SalesOrderID=... OrderDate=... CustomerID=... >
  <SalesPerson SalesPersonID=... />
  <OrderDetail SalesOrderID=... LineTotal=... ProductID=... OrderQty=... />
  <OrderDetail SalesOrderID=... LineTotal=... ProductID=... OrderQty=.../>
      ...
</OrderHeader>
<OrderHeader ...</OrderHeader>

A seguinte consulta em modo EXPLICIT constrói este XML. A consulta especifica Tag valores de 1 para o <OrderHeader> elemento, 2 para o <SalesPerson> elemento e 3 para o <OrderDetail> elemento. Como <SalesPerson> e <OrderDetail> são irmãos, a consulta especifica o mesmo Parent valor de etiqueta 1 identificando o <OrderHeader> elemento.

USE AdventureWorks2022;
GO
SELECT  1 as Tag,
        0 as Parent,
        SalesOrderID  as [OrderHeader!1!SalesOrderID],
        OrderDate     as [OrderHeader!1!OrderDate],
        CustomerID    as [OrderHeader!1!CustomerID],
        NULL          as [SalesPerson!2!SalesPersonID],
        NULL          as [OrderDetail!3!SalesOrderID],
        NULL          as [OrderDetail!3!LineTotal],
        NULL          as [OrderDetail!3!ProductID],
        NULL          as [OrderDetail!3!OrderQty]
FROM   Sales.SalesOrderHeader
WHERE     SalesOrderID=43659 or SalesOrderID=43661
UNION ALL
SELECT 2 as Tag,
       1 as Parent,
        SalesOrderID,
        NULL,
        NULL,
        SalesPersonID,
        NULL,
        NULL,
        NULL,
        NULL
FROM   Sales.SalesOrderHeader
WHERE     SalesOrderID=43659 or SalesOrderID=43661
UNION ALL
SELECT 3 as Tag,
       1 as Parent,
        SOD.SalesOrderID,
        NULL,
        NULL,
        SalesPersonID,
        SOH.SalesOrderID,
        LineTotal,
        ProductID,
        OrderQty
FROM    Sales.SalesOrderHeader SOH,Sales.SalesOrderDetail SOD
WHERE   SOH.SalesOrderID = SOD.SalesOrderID
AND     (SOH.SalesOrderID=43659 or SOH.SalesOrderID=43661)
ORDER BY [OrderHeader!1!SalesOrderID], [SalesPerson!2!SalesPersonID],
         [OrderDetail!3!SalesOrderID],[OrderDetail!3!LineTotal]
FOR XML EXPLICIT;

Este é o resultado parcial:

<OrderHeader SalesOrderID="43659" OrderDate="2005-07-01T00:00:00" CustomerID="676">
  <SalesPerson SalesPersonID="279" />
  <OrderDetail SalesOrderID="43659" LineTotal="10.373000" ProductID="712" OrderQty="2" />
  <OrderDetail SalesOrderID="43659" LineTotal="28.840400" ProductID="716" OrderQty="1" />
  <OrderDetail SalesOrderID="43659" LineTotal="34.200000" ProductID="709" OrderQty="6" />
    ...
</OrderHeader>
<OrderHeader SalesOrderID="43661" OrderDate="2005-07-01T00:00:00" CustomerID="442">
  <SalesPerson SalesPersonID="282" />
  <OrderDetail SalesOrderID="43661" LineTotal="20.746000" ProductID="712" OrderQty="4" />
  <OrderDetail SalesOrderID="43661" LineTotal="40.373000" ProductID="711" OrderQty="2" />
  ...
</OrderHeader>