Weak dependecnies in the relational datamodel

  V.D. ThiN.K. Anh

 One of the main concepts in relational database theory is the full family of functional dependencies, that was first axiomatized by W. W. Armstrong [1]. The full family of dual, strong and weak dependecies have also been introduced and axiomatized in [2,3,4]. The logical structures of them have also been investigated in [5,6,7,8,9,10].

 In this paper, we give some results, that are related to weak dependencies. We give a necessary and sufficient condition for , and then we construct an effective combinatorial algorithm to detemine irredundant relation for an arbitrary given relation such that Connections between dependencies are investigated also.

 Gyenizse Pal 1996. Szeptember 4. Szerda 14:18:36 MET DST