When is it a look up table and when is it an real entity?
From: Emily Jones <emmersthejones_at_hotmail.com>
Date: Mon, 7 Jun 2004 00:19:10 +0100
Message-ID: <40c3a66a$0$58819$5a6aecb4_at_news.aaisp.net.uk>
That subject line will have Joe Celko apoplectic!!
Some attributes might be VIN, Fuel, Color. Some entity instances might be:
wvv2939-32-2993-2-90, Gasoline, Blue
wvv3942-3249--2830-2, Diesel, Red
Date: Mon, 7 Jun 2004 00:19:10 +0100
Message-ID: <40c3a66a$0$58819$5a6aecb4_at_news.aaisp.net.uk>
That subject line will have Joe Celko apoplectic!!
Let's say I have this thing. Oh, I don't know, a car. No, a vehicle. Can we
agree that is an entity type?Some attributes might be VIN, Fuel, Color. Some entity instances might be:
wvv2939-32-2993-2-90, Gasoline, Blue
wvv3942-3249--2830-2, Diesel, Red
I wanna make it easy to get the colors in. Keep a list of 'em somewhere. So is that an entity that has a many to one relationship to vehicle? Or do I just have a standalone table somewhere with a list of colours, grab one when I want it and shove it into the right vehicle field.
Which approach best? How to decide.
Yours, Em Received on Mon Jun 07 2004 - 01:19:10 CEST