“…It encompasses preference logics [23,19,13], preference reasoning [24,22,4], prioritized nonmonotonic reasoning and logic programming [5,6,21] and decision theory [7,8] (the list is by no means exhaustive). However, only a few papers [18,3,11,2,14,17] address the issue of user preferences in the context of database queries. Two different approaches are pursued: qualitative and quantitative.…”