Issues in the practical use of the OWA operators in fuzzy querying

Flexible querying of the relational databases is considered. The applicability of some non-standard, mainly linguistic quantifier driven aggregation, and via Yager's ordered weighted averaging (OWA) operators in particular, is shown. Their handling is studied with a special emphasis on the selection and tuning of the OWA operator that is appropriate for the user needs. We start with an OWA operator and intend to tune it to increase its ORness, but keeping the changes as limited as possible, or to preserve consistency of the changes. These tasks are defined as optimization problems. The discussion is illustrated on the example of the authors' FQUERY for Access system.