(Msg. 2) Posted: Thu Feb 17, 2005 4:17 pm
Post subject: Re: normalisation [Login to view extended thread Info.] Archived from groups: per prev. post (more info?)
Dear Alan, I'm sorry, but this is not my homework. I used this example
to ask what to do with independent attributes. Believe me or not
normalisation is sometimes pretty hard for 13 y/o kid.
(Msg. 3) Posted: Thu Feb 17, 2005 5:40 pm
Post subject: Re: normalisation [Login to view extended thread Info.] Archived from groups: per prev. post (more info?)
wrote in message
> the given relation is R(a,b,c,d) and fuctional dependencies: > a->b > b->c > bc->a > > question : what NF is the relation in ? > what can be said about a "d" attribute which is not involved in any FD? > > thanks for any help >
(Msg. 4) Posted: Thu Feb 17, 2005 8:40 pm
Post subject: Re: normalisation [Login to view extended thread Info.] Archived from groups: per prev. post (more info?)
Uh, let's try...
- Keys of relation are: AD, BD
- Only one Non-Key attribut is C
- In "B->C" exists partial dependency of Non-Key attribute "C" on the SubSet
of Key "BD" - so relation is not even in the 2NF
Drazen Zlatarek
wrote in message
> the given relation is R(a,b,c,d) and fuctional dependencies: > a->b > b->c > bc->a > > question : what NF is the relation in ? > what can be said about a "d" attribute which is not involved in any FD? > > thanks for any help > >> Stay informed about: normalisation
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