Re: equivalence of functional dependencies

I have tried an example from the elmasri book, perhaps somebody can pass judgement on my logic,

two sets of functional dependencies F= {A > C, AC > D, E > AD, E > H} and G = {A > CD, E > AH}. Check whether or not they are equivalent.

here I make conclusion that they are not equivalent,

E > AD, E > H will as union give me E > ADH

therefore E > AH not deductible

A > C, AC > D will not help to derive A > CD either,

thanks

Shannon

Jonathan Leffler wrote:
> shannon wrote:
>

>> FD has been bugging me for a month now,
>>
>> F = {A  -> BC, A  -> D, CD -> E}
>> G = {A -> BCE, A -> ABD, CD -> E}
>>
>> I have been told that the sets of functional dependencies above are 
>> equivalent, can anybody explain to me how I can come to this 
>> conclusion step by step,
>>
>> I understand that armstrong's axioms are used to come to the 
>> conclusion, I have seen these axioms written down,
>>
>> please use another example if you are in fear of doing 'homework'