Results 261 to 270 of about 5,936,360 (329)
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Preserving Functional Dependencies
SIAM Journal on Computing, 1981We show that functional dependency preservation can be tested in polynomial time. We show further that while finding a cover for all embedded dependencies is NP-complete, such a cover can be found in polynomial time if dependencies are preserved.
Beeri, C., Honeyman, P.
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Rationally Functional Dependence
Journal of Philosophical Logic, 2013The authors discuss functional dependencies, and compare ontological and rational dependencies. What I call ontological dependencies are the dependencies that are based on the state of nature. Rational dependencies, on the other hand, are game theoretical, and require a free will and a strategy-based approach.
Naumov, Pavel, Nicholls, Brittany
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Discovery Algorithms for Embedded Functional Dependencies
SIGMOD Conference, 2020Embedded functional dependencies (eFDs) advance data management applications by data completeness and integrity requirements. We show that the discovery problem of eFDs is NP-complete, W[2]-complete in the output, and has a minimum solution space that is
Ziheng Wei, Sven Hartmann, S. Link
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Efficient Discovery of Functional Dependencies on Massive Data
IEEE Transactions on Knowledge and Data EngineeringFunctional dependencies are the most common constraints in the design theory for relational databases, which have very important practical applications in many areas.
Xiaolong Wan +3 more
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An extension of classical functional dependency: dynamic fuzzy functional dependency
Information Sciences, 1999zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Ben Yahia, S., Ounalli, H., Jaoua, A.
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Distributed Discovery of Functional Dependencies
IEEE International Conference on Data Engineering, 2019We address the problem of discovering functional dependencies from distributed big data. Existing (non-distributed) algorithms such as FastFDs focus on minimizing computation.
Hemant Saxena +2 more
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Functional equations involving Sibuya’s dependence function
Aequationes mathematicae, 2018The authors consider the problem of solving the functional equation \(D_{\mathbf X}(x_1,x_2)=D_{{\mathbf X}_{(t_1,t_2)}}(x_1,x_2)\) for all \(x_1\), \(x_2\), \(t_1\), \(t_2\geq 0\), where \(D_{\mathbf X}(x_1,x_2)\) is the Sibuya's dependence function and \(\mathbf X\) and \({\mathbf X}_{(t_1,t_2)}\) are random vectors defined as \({\mathbf X}=(X_1,X_2)\
Nikolai Kolev, Jayme Pinto
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Enumeration Complexity of Conjunctive Queries with Functional Dependencies
Theory of Computing Systems, 2017We study the complexity of enumerating the answers of Conjunctive Queries (CQs) in the presence of Functional Dependencies (FDs). Our focus is on the ability to list output tuples with a constant delay in between, following a linear-time preprocessing. A
Nofar Carmeli, Markus Kröll
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Local XML functional dependencies
Proceedings of the fifth ACM international workshop on Web information and data management - WIDM '03, 2003Keys and functional dependencies play a fundamental role in relational databases where they are used in integrity enforcement and in database design. Similarly, these constraints will play a fundamental role in XML and recently keys and functional dependencies in XML have been defined.
Jixue Liu, Millist Vincent, Chengfei Liu
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Error-Robust Functional Dependencies
Fundamenta Informaticae, 2004A database user may be confronted with a relation that contains errors. These errors may result from transmission through a noisy channel, or they may have been added deliberately in order to hide or spoil information. Error-robust functional dependencies provide dependencies that still hold in the case of errors.
Hartmann, Sven +3 more
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