An approach to solve division-like queries in fuzzy object databases

The division operator is well known in the context of fuzzy relational databases. Fuzzy approaches to this operator can be found in the literature to solve flexible queries: these approaches try to compute to which extent each element of a candidate set is connected with a given (fuzzy) set of elements. This kind of queries is also interesting in the framework of fuzzy object databases, where the management of complex objects instead of plain tuples causes additional difficulties. The presence of fuzzily described objects in the database makes necessary to use suitable operators that take into account the resemblance that governs the comparison in the underlying reference universe. In this paper, we propose a method to solve this type of queries founded on the use of fuzzy inclusion operators. We study two different alternatives for the way resemblance is considered and we also analyze the role of cardinality in the process. © 2012 Elsevier B.V. All rights reserved.