I am trying to work with some example code. The tutorial indicates that the following SQL will compile and execute in SQL Server. I'm working in Oracle 8.0.5 and can't get it to work. My first impression is that the syntax for the subquery is invalid; I've never seen a subquery that isn't in a WHERE clause.

SELECT Parent.category_id, Parent.category_name,
(SELECT Count(*) FROM category_tree Child2,
category_tree Parent2
WHERE
Child2.StartBranch BETWEEN Parent2.StartBranch AND Parent2.EndBranch
AND Child2.category_id = Parent.category_id) TreeBranch

FROM category_tree Child, category_tree Parent
WHERE (Child.StartBranch BETWEEN Parent.StartBranch AND Parent.EndBranch)
AND (Child.category_id=2)
ORDER BY TreeBranch