About Querying Operations Against Possibilistic Databases

摘要

This paper is situated in the area of the so-called fuzzy databases, i.e., databases containing imprecise information. More precisely, the focus is put on the querying of such databases where ill-known attribute values are represented by possibility distributions. This paper investigates a query language with three operators: selection, projection and a join operator which allow to express queries involving several relations at a time. The key idea is to impose a strong connection between the relations manipulated by (in particular resulting from) the operators and their interpretation in terms of more or less possible worlds.