Re: Treating addresses in 3NF?
Date: Wed, 13 Nov 2002 14:51:31 -0000
Message-ID: <aqtovb$13ra$1_at_sp15at20.hursley.ibm.com>
"Paul" <pbrazier_at_cosmos-uk.co.uk> wrote in message
news:51d64140.0211130524.537bf798_at_posting.google.com...
>
> Now AB12 will always be in the county of Countyshire.
Well 'AB12' -> POSTAL_TOWN
and POST_TOWN -> COUNTY
and COUNTY -> COUNTRY
but AB12 does not impliy that your house is actually in COUNTY, nor for that matter COUNTRY.
E.g. Search for 'HOME FARM' in 'SY13' on the address finder on www.royalmail.com and, although they do not show COUNTRY, I know that half of those farms are in Wales and half in England!
If anyone is serious about UK postal addresses, you need to digest:
http://www.royalmail.com/docContent/other/Downloadable_Files/PAF_Digest_Issue_ 5_0.pdf
And try to find all the hidden functional dependencies :-)
Then try the same for the 200 or so other other postal address 'standards' around the world.
Regards
Paul Vernon
Business Intelligence, IBM Global Services
Received on Wed Nov 13 2002 - 15:51:31 CET