Foundations of Preferences in Database Systems

Publisher Summary

This chapter presents a rich preference model tailored for database systems. Preferences as strict partial orders have an intuitive semantics; they may be subjective from daily life experiences, driven by personal intentions, or due to technical constraints. The extensible preference model both unifies and extends existing approaches for non-numerical and numerical ranking and opens the door for a new discipline called preference engineering. Preferences as strict partial orders possess a Spartan formal basis being the key for a preference algebra, where many laws are valid that are valuable for preference query optimizers. Personalization of e-services poses new challenges to database technology, demanding a powerful and flexible modeling technique for complex preferences. Preference queries have to be answered cooperatively by treating preferences as soft constraints, attempting a best possible matchmaking.