hi,
i am a engineering student in india.i have a doubt regarding the database design.

in the logical database design we use the concept of functional dependencies and the closure using Amstrong's axioms . What is the basic necessity to find the closure of the functional dependencies.

one more Question::
if we have a relation R(a,b,c,d,e) and a set of functional dependencies F. when we want to update is it sufficient if it satisfies F or do we need to satisfy the closure of F and why?

whoever is interested please give a reply to m mail swaroopreddy_k@yahoo.co.uk

thank you

that's curious, you aren't the only one recently with a question about armstrong

maybe you could get together with this person -- http://www.dbforums.com/t1084083.html

Hi,
i suggest you take a look at this link i found in google.
http://www.dbis.informatik.hu-berlin.../Maier/C04.pdf
its very helpful, and i predict that it will answer your questions.
p.s if you find the answers would you mind posting it?
best wishes
b737

i coped on to what i asked in the above link.thanks for the help.