Question

How do I wrap OldValue in a CDATA?

SELECT
1 AS Tag,
0 AS Parent,
(
    SELECT PositionDescription AS 'data()'
     FROM dbo.Project where ID = 32
     FOR XML PATH('')
) AS 'PositionDescription!1!OldValue!CDATA'
FOR XML EXPLICIT, TYPE 

Answer 1

Just drop the TYPE keyword. And use the raw string rather than XML in the subquery

SELECT
1 AS Tag,
0 AS Parent,
(
    SELECT PositionDescription
      FROM dbo.Project where ID = 32
) AS [PositionDescription!1!OldValue!CDATA]
FOR XML EXPLICIT

Sample & Output

create table Project (PositionDescription varchar(100), id int)
insert project select 'abc<test>', 32
---

<PositionDescription>
  <OldValue><![CDATA[abc<test>]]></OldValue>
</PositionDescription>