Re: A Simple Notation

From: paul c <toledobythesea_at_oohay.ac>
Date: Sat, 07 Jul 2007 15:30:32 GMT
Message-ID: <skOji.94053$NV3.69985@pd7urf2no>

Brian Selzer wrote:
> "paul c" <toledobythesea_at_oohay.ac> wrote in message
> news:PAAji.92566$xq1.59731_at_pd7urf1no...
>

>>Brian Selzer wrote:
>>
>>>"David Cressey" <cressey73_at_verizon.net> wrote in message 
>>>news:eirji.2$475.1_at_trndny04...
>>>

...

>>I wonder when, in the course of the usual human affairs as they involve 
>>the basic relational dbms op's, does it make sense to think of infinite 
>>domains?  Isn't it usually sufficient, as far as algebra is concerned, to 
>>pretend they are finite?
>>

>
>
> Why limit yourself to what can be represented in a computer? An algebra
> that supports relations with infinite cardinality or degree can certainly
> support any relation that can be represented in a computer.

As somebody here said (perhaps it was you, I forget), it seems important to separate relational operators from the rest of a language where we can do non-relational things, such as arithmetic addition. As far as a dbms that stores extensions/propositions is concerned, I don't see that it is possible to store infinite sets of values, so I wouldn't know how to implement that.

p Received on Sat Jul 07 2007 - 10:30:32 CDT