[tmql-wg] tolog 0.1 draft specification

Robert Barta rho@bigpond.net.au
Thu, 10 Apr 2003 08:54:50 +1000

On Thu, Mar 13, 2003 at 11:02:31PM +0100, Lars Marius Garshol wrote:
> I've now written up the beginnings of a draft for the tolog query
> language which shows the functionality of the current version of the
> language (0.1).
> This is still just a draft, but if you are interested you can read it
> at:
>   <URL: http://www.ontopia.net/topicmaps/materials/tolog-spec.html >
> Comments can be made here or to the author.


2.1 Operator clause: In [7] there is no explicit '='. If this is intended,
    one is supposed to express equality by unification?

2.1 Or clauses: Syntax cant be right. '}' is probably wrong.

2.1 You have the 'not' in front of a clause list. If I want a clause
    to be negated I have to write

      not ( my-clause-here )

    and not

      not my-clause-here

    ? And all the clauses in the ()'s are ANDed before the not?

2.1 In [18] I miss a []+ somewhere. And can't strings contain escaped \"'s?

2.2 Comment: the keyword 'FROM' seems to have a rather different
    meaning than the 'FROM' in SQL. In SQL I refer to a set of tables;
    in tolog it is predicates in clauses.

    In the query I wonder how to address a particular map.

3 : "Query results consist of a list of sets of (variable, value) bindings."

    So : one variable binding is a tuple (var, val)
         one match consists of several such tuples
         one result is a list of matches


4.2. direct-instance-of

    Working with AsTMa! I started to wonder whether there is such thing as
    a "direct instance of". Yes, someone can author it, but who knows what
    happens over the course of time: New intermediate topics might be

    What I am saying is that this concept is not robust. In AsTMa!? I
    have not allowed to base queries on it.

4.2 "...represented directly..."

    What do you mean here?