Consider the relations r(A, B) and s(B, C), where s.B is a primary key and r.B is a foreign key referencing s.B. Consider the queryQ:

𝜎𝐵<5(𝑟) 𝐿𝑂𝐽 𝑠

Consider the relations r(A, B) and s(B, C), where s.B is a primary key

1.	Consider the relations r(A, B) and s(B, C), where s.B is a primary key and r.B is a foreign key referencing s.B. Consider the queryQ:
A.	𝜎𝐵<5(𝑟 ⋈ 𝑠)
B.	𝜎𝐵<5(𝑟 𝐿𝑂𝐽 𝑠)
C.	𝑟 𝐿𝑂𝐽 (𝜎𝐵<5(𝑠))
D.	𝜎𝐵<5(𝑟) 𝐿𝑂𝐽 𝑠
Answer» D. 𝜎𝐵<5(𝑟) 𝐿𝑂𝐽 𝑠

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Consider the relations r(A, B) and s(B, C), where s.B is a primary key and r.B is a foreign key referencing s.B. Consider the queryQ:

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