A Generalized Left-Hand Side and Right-Hand Side Conflicts Decision Algorithm of F with Inside Conflicts

The acyclic property of database data structure is an important property of the database theory and application. How to make an acyclic decomposition of the database schema is a relatively complex problem, and more complex is the α-acyclic decomposition problem when there exist inside conflicts in FD set F. Discussed in this paper is that when there exist generalized left-hand side conflicts or generalized right-hand side conflicts in FD set F which has inside conflicts, the relationship between the generalized left-hand side or generalized right-hand side conflicts and the symmetrical left-hand side attribute set, and the existing condition and property of the symmetrical left-hand side attribute set. The corresponding concepts, theorems and proof are also given. On this basis, a decision algorithm of the existence of generalized left-hand side or generalized right-hand side conflicts is presented. The correctness verification and algorithm analysis of the above mentioned algorithm are presented too.