[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.
Lars,
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
Right?
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
introduced.
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?
\rho