# Question

Let the following relation schemas be given:

R = (A, B, C)

S = (D, E, F) Let relations r(R) ands(S) be given. Give expressions in QBE, and Data log equivalent to each of the following queries:

a. IIA(r)

b. σB =17 (r)

c. r × sd. IIA,F (σC =D(r × s))

R = (A, B, C)

S = (D, E, F) Let relations r(R) ands(S) be given. Give expressions in QBE, and Data log equivalent to each of the following queries:

a. IIA(r)

b. σB =17 (r)

c. r × sd. IIA,F (σC =D(r × s))

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