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GATE CSE 1988 | Question: 12i

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What are the three axioms of functional dependency for the relational databases given by Armstrong.
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1. AXIOM OF REFLEXIVITY

If $Y\subseteq X$ then   $X\rightarrow Y$

2. AXIOM OF AUGMENTATION

If   $X\rightarrow Y$ then   $XZ\rightarrow YZ$ for any Z

3. AXIOM OF TRANSITIVITY

If   $X\rightarrow Y$  and   $Y\rightarrow Z$  then   $X\rightarrow Z$
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