Traditional Relational Database Management System (RDBMS) query languages suffer from rigidity. There are some proposals for solving this problem using fuzzy sets, such as SQLf. The trouble with fuzzy querying languages is that they have been proposed to be implemented with loosely or middle coupling architecture, adding undesired overhead. This paper deals with the theoretical and pragmatic foundations for providing SQLf with tight coupling. We present an original experimental study that evidences performance of tight coupling approach for fuzzy querying.