Re: foreign key constraint versus referential integrity constraint
Date: Sun, 25 Oct 2009 23:41:42 -0700 (PDT)
On Oct 25, 7:44 am, Bob Badour <bbad..._at_pei.sympatico.ca> wrote:
> com..._at_hotmail.com wrote:
> > On Oct 24, 8:56 pm, Bob Badour <bbad..._at_pei.sympatico.ca> wrote:
> >>What reason would one have to define an equality comparison to compare
> >>employee ids with department ids or with names? Or charge with current
> >>or potential? Or age with price?
> > shoot your age and you are worth your weight in gold.
> My age in what measure? Years? Integral or rational? If integral,
> cardinal or ordinal? According to what calendar?
I was just (humorously seriously) giving examples of such peculiar comparisons that I'd say have reasons. Otherwise I agree with you. Certainly the corresponding expressions depend on the variable and function predicates.
philip Received on Mon Oct 26 2009 - 07:41:42 CET