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The study of joins in fuzzy relational databases. (English) Zbl 0635.68116

Summary: It is often necessary to join (naturally) two or more fuzzy relations to answer a user’s query. However, the result of a join may not be what one expects. In this paper, we study the decomposition problem of fuzzy relation schemes. We show that the algorithm proposed by A. V. Aho, C. Beeri and J. D. Ullman [ACM Trans. Database Syst. 4, 297- 314 (1979)] to test lossless join decomposition for classical relations can be applied in the fuzzy domain when particularizations are induced by functional dependencies.

MSC:

68P20 Information storage and retrieval of data
68P05 Data structures
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References:

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