  Diversification of DB applications highlighted the limitations of relational
database management system (RDBMS) particularly on the modeling plan. In fact,
in the real world, we are increasingly faced with the situation where
applications need to handle imprecise data and to offer a flexible querying to
their users. Several theoretical solutions have been proposed. However, the
impact of this work in practice remained negligible with the exception of a few
research prototypes based on the formal model GEFRED. In this chapter, the
authors propose a new approach for exploitation of fuzzy relational databases
(FRDB) described by the model GEFRED. This approach consists of 1) a new
technique for extracting summary fuzzy data, Fuzzy SAINTETIQ, based on the
classification of fuzzy data and formal concepts analysis; 2) an approach of
assessing flexible queries in the context of FDB based on the set of fuzzy
summaries generated by our fuzzy SAINTETIQ system; 3) an approach of repairing
and substituting unanswered query.
