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AMW
2009

Schema Design for Uncertain Databases

9 years 11 months ago
Schema Design for Uncertain Databases
We address schema design in uncertain databases. Since uncertain data is relational in nature, decomposition becomes a key issue in design. Decomposition relies on dependency theory, and primarily on functional dependencies. We study the theory of functional dependencies (FDs) for uncertain relations. We define several kinds of horizontal FDs and vertical FDs, each of which is consistent with conventional FDs when an uncertain relation doesn't contain any uncertainty. In addition to standard forms of decompositions allowed by ordinary relations, our FDs allow more complex decompositions specific to uncertain data. We show how our theory of FDs can be used for lossless decomposition of uncertain relations. We then present algorithms and complexity results for three fundamental problems with respect to FDs over ordinary and uncertain relations: (1) Testing whether a relation instance satisfies an FD; (2) Finding all FDs satisfied by a relation instance; and (3) Inferring all FDs th...
Anish Das Sarma, Jeffrey D. Ullman, Jennifer Widom
Added 16 Feb 2011
Updated 16 Feb 2011
Type Journal
Year 2009
Where AMW
Authors Anish Das Sarma, Jeffrey D. Ullman, Jennifer Widom
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