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Title: Một vài kết quả liên quan đến bài toán thành viên trong lớp phụ thuộc hàm
Authors: Lê, Đức Minh
Keywords: Toán học;Lớp phụ thuộc hàm
Issue Date: 1996
Publisher: Đại học Quốc gia Hà Nội
Abstract: The main purpose of the paper is to study some problems related to the membership problem in the class of functional dependencies. In the paper a way of proving the equivalence of consequences by Armstrong axiomas and by logical values on the basic of the algorithm for finding the closure of a set of attributes. Such as, for a set F of functional dependencies and a functional dependencies and a functional dependency f then the three followings are equivalent: 1) F implies f by Armstrong axiomas, 2) F implies f by logical values, and 3) F implies f by relations. The paper give a necessary and sufficient condition for testing that whether a relation R satiesfies the set F of functional dependencies or not. The paper also mentions some idea for implementing the algorithm to test deduction of a functional dependency from the given set of functional dependences.
Appears in Collections:Natural Sciences and Technology

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