cffrost2 - 10:33 pm on Sep 12, 2012 (gmt 0)
I think the confusion here is the need to display all rows from the column "category". The problem with that statement is every row in the "pages" table has a field for a category value. So technically, you would display all rows in the pages table regardless of the column "category" because the returned results would include the "category" values from each row in the "pages" table.
Does that make sense? My question to you is, are you looking to only display the category values from each row in the pages table without duplicates? If so, topr8 is pretty much on point.