"GROUP BY" question

Sorry for the simple question. How can I get the forth line (A or B) using SQL statements?

category count

   A              5
   B             10
A or B         15

The following statement seems not to work.

select category count(*) from collection_data group by category
having category = 'A' or category = 'B' Received on Mon Feb 21 2000 - 17:03:19 CST