How to return XML from SQL Server 2008 that is structured with multiple selections sharing a common parent

Question

I've tried using "FOR XML PATH", "FOR XML EXPLICIT" and "FOR XML AUTO" but the data is never structured with the correct heirarchy.

Basically, I have one parent table (Customers) and 3 child tables. Each table has a customerid column. There is a one-to-many relationship from the Customers table to each of the 3 child tables.

As a mock example, I have a parent "Customers" table, and I have 3 other tables - Products, Hobbies and Vehicles - all related to the Customers table by a customerid.

What is the SQL code to achieve the following kind of structure -

<Customers>
    <Customer customerid="1" name="Fred">
       <Products>
           <Product productname="table" />
           <Product productname="chair" />
           <Product productname="wardrobe" />
       </Products>
       <Hobbies>
           <Hobby hobbyname="Golf" />
           <Hobby hobbyname="Swimming" />
       </Hobbies>
       <Vehicles>
           <Vehicle name="Car" color="Red" />
           <Vehicle name="Bicycle" color="Blue" />
       </Vehicles>
    </Customer>
    <Customer customerid="2" name="Sue">
       <Products>
           <Product productname="CD player" />
           <Product productname="Picture frame" />
       </Products>
       <Hobbies>
           <Hobby hobbyname="Dancing" />
           <Hobby hobbyname="Reading" />
       </Hobbies>
       <Vehicles>
           <Vehicle name="Car" color="Yellow" />
       </Vehicles>
    </Customer>
</Customers>

Answer 1

Try something like this - it uses FOR XML PATH and subselects to create the "linked" sub-nodes for a given customer (I limited this to two sub tables - but you should get the "gist" of it and be able to extend it to any number of linked subtables):

SELECT
    CustomerID AS '@CustomerID',
    CustName AS '@Name',

    (SELECT ProductName AS '@productname'
     FROM dbo.Products p
     WHERE p.CustomerID = c.CustomerID  
     FOR XML PATH('Product'), TYPE) AS 'Products',

    (SELECT HobbyName AS '@hobbyname'
     FROM dbo.Hobbies h 
     WHERE h.CUstomerID = c.CustomerID
     FOR XML PATH('Hobby'), TYPE) AS 'Hobbies'
FROM
    dbo.Customers c
FOR XML PATH('Customer'), ROOT('Customers')

Gives me an output something like:

<Customers>
  <Customer CustomerID="1" Name="Fred">
    <Products>
      <Product productname="Table" />
      <Product productname="Wardrobe" />
      <Product productname="Chair" />
    </Products>
    <Hobbies>
      <Hobby hobbyname="Golf" />
      <Hobby hobbyname="Swimming" />
    </Hobbies>
  </Customer>
  <Customer CustomerID="2" Name="Sue">
    <Products>
      <Product productname="CD Player" />
      <Product productname="Picture frame" />
    </Products>
    <Hobbies>
      <Hobby hobbyname="Dancing" />
      <Hobby hobbyname="Gardening" />
      <Hobby hobbyname="Reading" />
    </Hobbies>
  </Customer>
</Customers>