Question: Let R be a relation schema with a set F of FDs. Prove that the decomposition of R into R1 and R2 is lossless-join if

Let R be a relation schema with a set F of FDs. Prove that the decomposition of R into R1 and R2 is lossless-join if and only if F+ contains R1 ∩ R2 → R1 or R1 ∩ R2 → R2.

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