Re: a union is always a join!
Date: Wed, 18 Mar 2009 22:13:04 -0700 (PDT)
Message-ID: <1dda2ed8-532f-4f11-9189-e0d237d3fc8a_at_q30g2000prq.googlegroups.com>
On Mar 18, 10:04 am, paul c <toledobythe..._at_oohay.ac> wrote:
> If you're saying you're not sure what relational assignment is, it is
> the assignment of a relation value to a variable, aka pointer, ie., it
> is a language device. Don't confuse relational assignment with any
> of the relational operators, which involve no notion of pointers. I
> wish people would clarify whether they are talking about the RM or
> about some language or other.
I don't think assignment concept, in general, and relational assignment, in particular, is useful anywhere beyond programming environment. We have relation as function of time, and describe relation evolution in terms of transitional constraints. This is in the same spirit as dynamical systems are defined with differential equations. I see no assignment concept in the latter, this is why I assume it is not important in relational theory as well. Received on Thu Mar 19 2009 - 06:13:04 CET