Re: model inherited object
Date: 21 Jun 2006 13:36:50 -0700
Message-ID: <1150922210.545792.11190_at_u72g2000cwu.googlegroups.com>
>> I have many databases that want access to some relatively static data that is relevant to all of them i.e Location. Each of these database represents a period in time, 2005, 2006 etc and the locations will remain pretty much the same. But say LOC01 has 200 sq ft in 2005 but in 2007 (because of building work) it will have 400
sq ft. However it also has 2 toilets (which have not changed because of
the work). <<
That is a temporal problem and not an OO problem. This is a job for Rick Snodgrass and SQL/MM proposals {play fanfare here} !!
>> So I record tuple X as (ID,Sq Ft, Toilets, ValidFrom) as LOC01 - 200 - 2 - 2005 <<
>> .. in fact those 2 toilets are inherited <<
That is not quite what I had in mind when I my mother to leave me the family porcelain :) Sorry, too good a straight line not to use it. This is change to the same entity over time and not OO inheriting.
>> So, how should this be done? <<
Procedures that build a new row with the proper time stamps, the changes and the "un-changes" in it. Received on Wed Jun 21 2006 - 22:36:50 CEST