[AccessD] Access and SQL Server

Yelp, yelp, and yelp! Hi Deb!!!

Susan H. 


> 1.  Real data can ALWAYS change.  I do not care how immutable it is 
> supposed to be, data changes.  Just ran into a problem in reports out of 
> a CRM database.  One magazine has changed names 3 times in 8 years.  
> They still want info tracked together, but the natural key of a short 
> code based on the name has changed (sigh).
> 2.  Real Data is subject to typos.  Even the best typist can realize a 
> problem happened after data has been entered.  Fix it and the 
> relationship is crap without cascade updates.
> 3.  Real data is never as unique as you may think.  This is why natural 
> keys usually evolve into compound keys.  Had a patent database that used 
> docket numbers as a natural key.  As they supported additional 
> countries, they added country.  As addendum were added to the patent, 
> refines were added.  Now this 3 field compound key was a nightmare to 
> work with.  To top it off, you guessed it, problem 1 reared it's head 
> too.  Rare occurrence, but in a database of almost 100,000 patents, it 
> probably occurred a few times a month.  Headache every time it happened.