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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 query Q: ? ⋈ (??<5(?)) Let LOJ denote the natural left outer-join operation. Assume that r and s contain no null values. Which one of the following queries is NOT equivalent to Q?

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 query Q: ? ⋈ (??<5(?)) Let LOJ denote the natural left outer-join operation. Assume that r and s contain no null values. Which one of the following queries is NOT equivalent to Q? Correct Answer 𝑟 𝐿𝑂𝐽 (𝜎<sub>𝐵</sub><sub>&lt;5</sub>(𝑠))

? ??? (??<5(?)) will include record with b> = 5 but other three queries will not.

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