Let the following relation schemas be given R A B C
Let the following relation schemas be given R A B C
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 the tuple relational calculus that is equivalent to each of the following:
a. II A(τ)
b. σB =17 (τ)
c. τ × s
d. IIA, F (σC =D(τ × s))