Oracle FAQ | Your Portal to the Oracle Knowledge Grid |
Home -> Community -> Usenet -> c.d.o.server -> Re: Beginner help needed in database design
Mark A wrote:
> "Frank van Bortel" <fvanbortel_at_netscape.net> wrote in message
> news:ctqf0h$2ln$1_at_news1.zwoll1.ov.home.nl...
>
>>SSN is a prime example is a technical key. Why is >>it people do not have a problem recognizing me by name, >>but computers do? >>-- >>Regards, >>Frank van Bortel
Chances are smaller than the number of people on this planet, that is not unique.
But - it is not compact; in the times memory was scarce
it surely would not have been acceptable. So, take a number.
Nice and easy, small, and guaranteed to be unique on top of
it all. And we call it: number.
And as this particular number was invented by the (US) Social
Service, let's call it a Social Security Number.
I don't have one, but I live in a country with a civilized social security system :^) I've other numbers attached to me...
But that is what a technical key is: a meaningless number (BTW: is SSN really meaningless, or is it coded?), instead of (mostly many) fields, together making up a unique identifier.
-- Regards, Frank van BortelReceived on Wed Feb 02 2005 - 15:36:22 CST