Write a domain relational calculus query that is equivalent to the following algebraic expressions:
a. R ? S
b. R/S, where relation R has attributes A, B and S has only one attribute, B.
a.
{X1,...,Xn | R(X1,...,Xn) AND NOT(S(X1,...,Xn)) }
b.
{A |?B ? S (R(A, B )) }
Computer Science & Information Technology
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