left outer join

Question

Find the equivalent Tuple Relational Calculus query for the following:

R ⟕ S , where R(A, B) and S(A, C) are the relations and ⟕ is the left outer join symbol in Relational Algebra.

Comments

Check it below link 

https://gateoverflow.in/166695/tuple-calculus

Answer 1

R ⟕ S : {t | ∃ r $\epsilon R$ , ∃ s $\epsilon S$ (r[A]=s[A] ^ t[A]=r[A] ^ t[B]=r[B] ^ t[C]=r[C] ) $\vee$ ∃ r $\epsilon R$ ( ¬∃ s $\epsilon S$ (r[A]=s[A] ^ t[A]=r[A] ^ t[B]=r[B] ^ t[C]=null))}