Question

I need a nudge in the right direction here. Simplified data looks like:

ItemId|ItemName|ObjectId|ObjectName
    1 |  Alpha |      1 |  Alpha-1
    1 |  Alpha |      2 |  Alpha-2
    2 |   Beta |      3 |   Beta-1
    2 |   Beta |      4 |   Beta-2

And my target xml needs to be:

<Root>
  <Items>
    <Item>
      <id>1</id>
      <name>Alpha</name>
    </Item>
    <Item>
      <id>2</id>
      <name>Beta</name>
    </Item>
  </Items>
  <Objects>
    <Object>
      <id>1</id>
      <item_id>1</item_id>
      <name>Alpha-1</name>
    </Object>
    <Object>
      <id>2</id>
      <item_id>1</item_id>
      <name>Alpha-2</name>
    </Object>
    <Object>
      <id>3</id>
      <item_id>2</item_id>
      <name>Beta-1</name>
    </Object>
    <Object>
      <id>4</id>
      <item_id>2</item_id>
      <name>Beta-2</name>
    </Object>
  </Objects>
</Root>

I am having trouble with the FOR XML statement syntax that will allow this kind of break out between the Items section and the Objects section. I know how to code each section individually (the Objects one anyway), but do not know how to get this stacked output. Can I do this from the single View shown here or do I need split things up and them splice the xml back together somehow?

Answer 1

Yes, you need to “split things up and then splice the xml back together somehow?”. You need two queries, one for Items and one for Objects.
Here is a way to do just that.

declare @T table
(
  ItemId int,
  ItemName varchar(10),
  ObjectId int,
  ObjectName varchar(10)
)


insert into @T
select    1 ,  'Alpha',       1,   'Alpha-1' union all
select    1 ,  'Alpha',       2,   'Alpha-2' union all
select    2 ,   'Beta',       3,    'Beta-1' union all
select    2 ,   'Beta',       4,    'Beta-2'


select 
  (
  select ItemId as id,
         ItemName as name
  from @T
  group by ItemId, ItemName
  for xml path('Item'), root('Items'), type
  ),
  (
  select ObjectId as id,
         ItemId as item_id,
         ObjectName as name
  from @T
  for xml path('Object'), root('Objects'), type
  )
for xml path('root')