[AccessD] Should Business use Access?

Thank you, Arthur, for showing me (once again) something I had not 
thought of.  I will incorporate that concept of the Point in Time into 
my work from now on.
TNF

Tina Norris Fields
tinanfields-at-torchlake-dot-com
231-322-2787

On 5/6/2014 5:41 PM, Arthur Fuller wrote:
> And none of this addresses the PITA issue (Point In Time Architecture),
> which basically says that the traditional relational concepts of Insert and
> Update and Delete are destructive of what data existed a moment ago. That
> is a very significant problem and requires a whole lot of planning, but to
> oversimplify, it means that Updates and Deletes are forbidden, and that
> every table in the DB be able to handle this. That means that every table
> has a pair of date fields (call them EffectiveDate and EndDate), and that
> all queries respect these fields. For example, take your average
> 50-year-old medical patient: she has probably had a few family physicians,
> optometrists and so on, due to moving to Seattle for a new job and a year
> or two later it's Denver.
>
> What this sort of database requires is the ability to wind the clock back
> to 2002, say. That is flatly impossible with the traditional Insert,
> Update, Delete model. The only way this can be handled is the PITA model:
> every table has EffectiveDate and EndDate columns and every query and
> stored procedure respects these columns. Who was your dentist in 2004? Who
> sold you that Ford that you gave to your daughter in 2012? Where did you
> live in 1999 and who was your physician at that time?
>
>
>
> Arthur
>
>
>