Preferences and bipolarity in query languages

Abstract

The integration of user preferences into queries addressed to a relational database management system allows to obtain more relevant answers. This paper is a short review of the different languages (PreferenceSQL and SQLf) proposed to integrate users' preferences inside queries. A particular attention is put on the expression of preferences, and the impact it has on the result provided to the user. Two particular concepts are dealt with : commensurability and bipolarity. This framework can be the base for an extended SQLf language.