[KLUG Programming] questions on picking data types

[Robert G. Brown]

On Thu, 15 Jul 2004 08:12:05 -0400, Adam Tauno Williams <awilliam at whitemice.org> wrote:

>> >> > If not, then it probably makes more sense to just store the
>> >> > 9-digit SSN as an INT.  That way when you need to retrieve a row
>> >> > ...
>> Oh, I can't WAIT for them to add a digit! :)
>Thats actually not so funny,...
Well, I didn't post it merely for belly laughs; my smiley was intended to cheer
up those of us who have been through these basic kinds of data transformations
in the past, and I listed towo of 'em.

> they've talked about doing so in the past. 
On several oocasions, sometimes to increase the information content.

>And SSN numbers are already not unique.
Right, they do have to be unique only by tense, so to speak. Internally,the
SSA handles them differently.

>How many COBOL programs will get modified to do SSNs as ######-####
>instead of ####-##-#### in order to squeeze in another digit without
>having to refactor all those SCREEN stanzas?  Thats my question.  I love
>COBOL programmers, they are just so darn "creative".
Well, it wouldn't be so bad if it were "merely" confined to COBOL programmers.
The fact is that a lot of these kinds of changes have profund and implicit
effects that people don't think of when they are examining a problem. I recall
that during some of the Y2K work, we left display data formats the same, and 
focused on altering the internal structure and behavior of things (oh, we
would sometimes have to alter display routines to keep things looking the 
same, accounting forthe different internal data representation). To ease the 
tedium, we decided to see what it would take to deal with all of these things
well, and it turned out to be quite a challenge.

This is where stuff like OO can really shine. When data elements are actually
wrapped up in objects, a lot of these problems go away, given that the object
definitions address these issues well. Having participated in developing systems
populated with objects so rigorously thought through, I can say that transforms
of this type are relatively easy to downright painless.

>> Y2K was so much fun, aswas the move from 8th the decimal on the exchanges...
>I'm waiting for the NIDN (National ID Number) to get passed and replace
>the SSN - that will be fun!
Yes, more of the same kind of fun, especially if it comes with reduced levels
of restrictions on how these data items can be used, to match up databases
in local, state, corporate, and federal organizations. I'm sure all KINDS of
new and interesting reporting possibilities will be possible.

							Regards,
							---> RGB <---