Special Cases of Relative Object Qualification: Using the AMONG Operator

Fuzzy querying means selecting the database objects that more or less respect a non-Boolean condition. The relative object qualification is defined as a new kind of user’s preference expressing; related with this, the AMONG operator is able to compute the fulfillment degree of the relative selection criteria. Two special cases of the relative object qualification are discussed in the paper; they are referring to qualifying database objects relatively to particular values of other attributes. Solutions to model and to evaluate them are proposed.