Abstract
This paper reports an algorithm (DTV) for determining the minimal reduced-covering of an acyclic database scheme over a specified subset of attributes. The output of this algorithm contains not only minimum number of attributes but also minimum number of partial relation schemes. The algorithm has complexityO(⋎N⋎·⋎E⋎2), where ⋎N⋎ is the number of attributes and ⋎E⋎ the number of relation schemes. It is also proved that for Berge, γ or β acyclic database schemes, the output of algorithm DTV maintains the acyclicity correspondence.
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Liu Tieying received his B.S. and M.S. degrees from Mathematics Department of Inner Mongolia University in 1981 and 1989, respectively. He is currently an Associate Professor in the Department of Computer Science at Inner Mongolia University. He is a member of the Inner Mongolia Association for Computing Mathematics. His research interests include applied mathematics and theory of database.
Ye Xinming received his B.S. degree in mathematics from Inner Mongolia University in 1965. He is currently a Professor and Head of the Department of Computer Science at Inner Mongolia University. He is a member of Council of Chinese Computer Federation and Chairman of Association of Inner Mongolia Computer Sociaty. His research interests include software engineering, network protocols, distributed algorithms and database.
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Liu, T., Ye, X. An algorithm for determining minimal reduced-coverings of acyclic database schemes. J. of Comput. Sci. & Technol. 11, 347–355 (1996). https://doi.org/10.1007/BF02948478
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DOI: https://doi.org/10.1007/BF02948478