[tmql-wg] Result set requirements

Dmitry dmitryv@cogeco.ca
Thu, 26 Feb 2004 08:25:02 -0500

On Feb 26, 2004, at 4:10 AM, Rani Pinchuk wrote:

> As I see it, the constructors controls the way the data is presented,
> while the data itself is controlled by the query language. I would try
> to separate those two (so separating the logic from the presentation).
> Arguments for such separation can be found in the Skin and the
> Phrasebook design patterns
> (http://jerry.cs.uiuc.edu/~plop/plop2k/proceedings/proceedings.html)
Constructors have nothing to do with data presentation. They allow to 
create new objects.
These objects can be based on TMDM, XML DOM or other data models. They 
are data structures.

Pure "select" query languages  do not allow creation of  new objects. I 
see it as a problem for TMQL.

My proposal, I think,  has a good separation between "select" and 
"construct" parts. That's why it was easy to replace
XPath-like select language with Prolog-like select language

I think also that tolog can get additional power with such constructs 
as "for", "if", "every, some  ... satisfies".

Actually, TMTL does some of  that for tolog, I just try to generalize 
the idea of constructors.