Re: Has E/R had a negative impact on db?
From: paul c <toledobythesea_at_oohay.ac>
Date: Tue, 25 Apr 2006 02:12:23 GMT
Message-ID: <bAf3g.69640$WI1.43229_at_pd7tw2no>
>>Jan Hidders wrote:
>>
>>>JOG wrote:
>>>...
>>>about anything interesting in a database.
>>
>>Right, so your working definition is that entities are "things that can
>>be identified and which we would like to store information about in the
>>database". Relationships however are also things, they can be identifed
>>and we would like to store them - so the definition appears to be on a
>>sticky wicket.
Date: Tue, 25 Apr 2006 02:12:23 GMT
Message-ID: <bAf3g.69640$WI1.43229_at_pd7tw2no>
Jan Hidders wrote:
> JOG wrote: >
>>Jan Hidders wrote:
>>
>>>JOG wrote:
>>>...
>>>>the conclusion that you don't believe that we can store information
>>>The usual definition of 'entity' in the context of data
>>>modelling for database is something like "things that can be identified
>>>and which we would like to store information about in the database". If
>>>that's how I interpret your statement then you seem to be saying that
>>>you don't believe there are such things, and since we cannot store
>>>information about things we cannot identify, this leads inexorably to
>>>about anything interesting in a database.
>>
>>Right, so your working definition is that entities are "things that can
>>be identified and which we would like to store information about in the
>>database". Relationships however are also things, they can be identifed
>>and we would like to store them - so the definition appears to be on a
>>sticky wicket.
> > > Yes, relationships are a special kind of entity. Why do you think this > is problematic? ...
It may not be a problem in abstract philosophy but it seems a problem to me when one is trying to metaphorically describe things or make an analogy on a computer, where the advantage seems to come from initial reduction, not expansion. Shouldn't the opportune comparison be that an entity (if one thinks entities are needed for conversation) is a special case of a relationship?
p Received on Tue Apr 25 2006 - 04:12:23 CEST