Re: Newbie question on table design.
From: paul c <toledobythesea_at_oohay.ac>
Date: Fri, 27 Apr 2007 12:00:51 GMT
Message-ID: <TBlYh.134102$6m4.74371_at_pd7urf1no>
>>Cimode wrote:
>>
>>
>>>... Historising tables in any form of shape is a hack. If a
>>>DBMS requires so much operations to historize information what's the
>>>point using it in the first place?
>>>...
>>
>>Not entirely sure I understand this, but I suspect I agree. I think
>>keeping history involves a "separate" database, even though I don't have a
>>simple definition of what "separate" means in practice, only that
>>operations on separate db's mightn't always give the same results given
>>the same values.
>>
Date: Fri, 27 Apr 2007 12:00:51 GMT
Message-ID: <TBlYh.134102$6m4.74371_at_pd7urf1no>
Brian Selzer wrote:
> "paul c" <toledobythesea_at_oohay.ac> wrote in message > news:dwaYh.131520$DE1.106984_at_pd7urf2no... >
>>Cimode wrote:
>>
>>
>>>... Historising tables in any form of shape is a hack. If a
>>>DBMS requires so much operations to historize information what's the
>>>point using it in the first place?
>>>...
>>
>>Not entirely sure I understand this, but I suspect I agree. I think
>>keeping history involves a "separate" database, even though I don't have a
>>simple definition of what "separate" means in practice, only that
>>operations on separate db's mightn't always give the same results given
>>the same values.
>>
> > > Why would you need a "separate" database? I was under the impression that > all you need to do is to add a time dimension to each relation for which you > need to keep history. The additional dimension can be implemented as an > attribute with an interval data type. >
Sorry, I shouldn't have suggested you need a separate db. I agree interval data types (not just time) are needed by certain relations. I was imagining an extreme case which I'll have to think about a little more.
p Received on Fri Apr 27 2007 - 14:00:51 CEST