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Prove that the decomposition of r into r1 and r2 is lossless

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Reference no: EM13509339

1.Prove that an MVD X →→ Y over a relation R can be expressed as the join dependency ;: {XY, X(R − Y )}.

2.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.

Reference no: EM13509339

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