AUTOMATIC DISCOVERY OF CANDIDATE IN THE RELATIONAL DATABASES KEYS BY USING ATTRIBUTES SETS CLOSURE

The automation of database design, design weak points detection, re-engineering and schema modification, and normalization of the database systems became the crucial aspects in databases studies. In real applications databases the discovery of candidate keys is regarded as a challenge for the designers. This research proposes an algorithm to automate the discovery of the candidate keys in the databases depending on the attributes set closure and functional dependency, FD, rules. In this research, the functional dependency rules are regarded as production rules to product binary strings which represent the sets of attributes and the candidate keys. Representing the rules and the sets of attributes as binary string allows proposing novel string matching and ordered strings merging which linearly speed up the execution time according to the number of attributes and the number of functional dependency rules. The proposed system was tested successfully by using many actual and synthesis schemas and dependencies some of these schemas and dependencies include one hundred attributes and one hundred FD rules respectively.