An approach to competitive conditional fuzzy preferences in database flexible querying

This paper introduces a new type of database queries involving preferences. The idea is to consider competitive conditional preference clauses structured as a tree, of the type ldquopreferably P₁ or ... or P_n; if P₁ then preferably P_1,1 or ...; if P₂ then preferably P_2,1 or ...rdquo, where the P_ipsilas are not exclusive (thus the notion of competition). The paper defines the interpretation of such queries and outlines an evaluation technique that follows from it.