Let the following relation schemas be given: R = (A, B, C) S = (D, E, F)

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Let the following relation schemas be given:

R = (A, B, C)

S = (D, E, F)

Let relations r(R) and s(S) be given. Give an expression in SQL that is equivalent to each of the following queries.

a. п A(r)

b. σB = 17 (r)

c. r × s

d. IIA, F (σC =D(r × s))

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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 28, 2011 05:54 AM

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Let the following relation schemas be given: R = (A, B, C) S = (D, E, F)

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a II Ar select distinct A from ...View the full answer

Database System Concepts

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