Re: relational reasoning -- why two tables and not one?

From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Wed, 14 Oct 2009 23:44:15 -0300
Message-ID: <4ad68c83$0$23757$9a566e8b_at_news.aliant.net>


paul c wrote:

> Bob Badour wrote:
> 

>> ...
>> Even then, it is historical data. For the same donor, all the
>> information might be the same from one donation to the next, or it
>> might all be different. Assuming one wants to record the information
>> as it was (or as it was reported by the donor) at the time of the
>> donation, few if any functional dependencies are likely to exist.
>>
>> Unless, of course, one creates a temporal database, but even then, the
>> charity seems to collect no information about intervening points of
>> time so a temporal database seems inappropriate too.
> 
> I presume 'historical' means rows are 'written once', normally not 
> replaced. If so that would be a good word to use if it is in fact one of 
> the requirements.

We don't really have requirements. All we have are a handful of 3rd hand comments, but those comments do suggest the relation is historical. The database records donations made and replies sent. All past tense. Nothing to change or keep up to date. Just what happened at some point in the past--much like an audit trail. Received on Thu Oct 15 2009 - 04:44:15 CEST

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