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An improved Algorithm Based on Subset Closures for Synthesizing a Relational Database Scheme
November 1988 (vol. 14 no. 11)
pp. 1731-1738

An algorithm for synthesizing a better relational database scheme in elementary key normal form (EKNF) is developed. This algorithm eliminates not only extraneous attributes and other redundancies, but also superfluities from a given set of functional dependences (FDs), based primarily on subset closures, Hamiltonian cycles of FDs, and equivalent subsets of attributes. Following this algorithm, a better LR-minimum FD covering is obtained. A more practical and efficient method for designing a relational database scheme in EKNF is then provided. The time complexity of the algorithm is polynomial.

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Index Terms:
subset closures; relational database scheme; elementary key normal form; functional dependences; subset closures; Hamiltonian cycles; time complexity; computational complexity; database theory; relational databases; set theory
Citation:
C.-C. Yang, G. Li, P.A.-B. Ng, "An improved Algorithm Based on Subset Closures for Synthesizing a Relational Database Scheme," IEEE Transactions on Software Engineering, vol. 14, no. 11, pp. 1731-1738, Nov. 1988, doi:10.1109/32.9058
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