Computer Sciences > GATE 2026 SET-1 > Relational Algebra
Consider a relational database schema with two relations R(P, Q) and S(X, Y).

Let E = {⟨u⟩ | ∃v ∃w ⟨u, v⟩ ∈ R ∧ ⟨v, w⟩ ∈ S} be a tuple relational calculus expression.

Which one of the following relational algebraic expressions is equivalent to E?
A
ΠP(R ⋈R.P=S.X S)
B
ΠP(S ⋈S.X=R.Q R)
C
ΠP(R ⋈R.P=S.Y S)
D
ΠP(S ⋈S.Y=R.Q R)

Correct : b

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