SQL allows relations with duplicates. a. Define versions of the basic relational-algebra operations , , , ,

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SQL allows relations with duplicates.

a. Define versions of the basic relational-algebra operations σ, Π, ×, Π, −, ∪, and ∩ that work on relationswith duplicates, in a way consistent with SQL.

b. Check which of the equivalence rules 1 through 7.b hold for the multiset version of the relational-algebra defined in part a.

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Database System Concepts

ISBN: 978-0072554816

4th Edition

Authors: Henry F. Korth, S. Sudarshan

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Question Posted: Jan 29, 2011 01:42 AM

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SQL allows relations with duplicates. a. Define versions of the basic relational-algebra operations , , , ,

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a We define the multiset versions of the relationalalgebra operators here Given multiset relations r ...View the full answer

Database System Concepts

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