An extended Boyce-Codd normal form in fuzzy relational databases

Author

Chen, Guoqing ; Kerre, Etienne E. ; Vandenbulcke, Jacques

Author_Institution

Sch. of Econ. & Manage., Tsinghua Univ., Beijing, China

Volume

3

fYear

1996

fDate

8-11 Sep 1996

Firstpage

1546

Abstract

If the relation schemes of any fuzzy database are not properly designed certain anomaly problems may occur when the fuzzy database is updated or maintained. This is because some undesired relationships exist among attributes. Based on the notions of fuzzy functional dependency (FFD) and θ-keys, the Boyce-Codd normal form is extended to cope with the anomaly problems caused by partial and transitive FFDs of θ-prime on some θ-keys, thus resulting in θ-fuzzy Boyce-Codd normal form (θ-FBCNF). Furthermore, the relationship between θ-FBCNF and other existing fuzzy normal forms is analyzed, showing that θ-FBCNF reflects the strongest restriction for attributes. Finally an algorithm is provided that can decompose, in a lossless-join manner, any scheme into a number of θ-FBCNF schemes

Keywords

database theory; fuzzy set theory; knowledge representation; probability; relational databases; uncertainty handling; Boyce-Codd normal form; attributes; fuzzy functional dependency; fuzzy normal forms; fuzzy relational databases; fuzzy set theory; possibility distribution; Relational databases; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Fuzzy Systems, 1996., Proceedings of the Fifth IEEE International Conference on

Conference_Location

New Orleans, LA

Print_ISBN

0-7803-3645-3

Type

conf

DOI

10.1109/FUZZY.1996.552562

Filename

552562