Towards reconciling expressivity, efficiency and user-friendliness in database flexible querying

In this paper, we present an implementation strategy for a fuzzy querying system embedded in a regular DBMS. This system relies on the language SQLf that makes it possible to express a great variety of fuzzy queries. Experiments show that this implementation strategy induces performance gains with respect to existing strategies based on a loose (or milder) coupling between a fuzzy querying layer and a DBMS, that necessitate an external postprocessing so as to compute the result in the form of a fuzzy relation. We also describe a user-friendly interface aimed at helping nonexpert users express their fuzzy queries in an intuitive manner.