Các phụ thuộc yếu trong mô hình dữ liệu quan hệ
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DOI:
https://doi.org/10.15625/1813-9663/6/4/11151Abstract
One of the main concepts in relational database theory is the full family of functional dependencies, that was first axiomatized by W.W.Armstrong [1].
The full family of weak dependencies have also been introduced and axiomatized [4, 5].
In this paper, we give some new results about weak dependencies. We give a necessary and sufficient condition for W+R = W+, and then we construct an effective combinatorial algorithms to determine irredundant relation R’ for an arbitrary given relation R such that R’ Í R, W+R’ = W+R.
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Published
30-01-2018
How to Cite
[1]
V. D. Thi and N. K. Anh, “Các phụ thuộc yếu trong mô hình dữ liệu quan hệ”, JCC, vol. 6, no. 4, p. 27–32, Jan. 2018.
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Computer Science
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