Re: [Core] binding patterns (was: safety and external predicates)

As we discussed (a few months) earlier, binding patterns have no meaning
outside of a particular evaluation algorithm (procedural semantics). It is
therefore not clear how to incorporate them in the current spec, which is
supposed to be independent of the procedural things.

michael

On Tue, 12 Aug 2008 17:31:08 +0100
Axel Polleres <axel.polleres@deri.org> wrote:

> 
> (put the subject under a [Core] label.)
> 
> Binding patterns were mentioned a view times today, I thus try to 
> reformulate here a definition, which may be a helpful starting point 
> helpful in this context and which :
> 
> An external predicate with external schema
> 
>   ( X_1,....,X_n; pred(X_1,....,X_n) )
> 
> is  assigned with one or more binding patterns, where a binding pattern 
> is a vector {in,out}^n:
> 
> Any external predicate provides a way for deciding the truth value of an 
> output tuple depending on the extension of a set of input predicates and 
> terms. External predicates have a fixed interpretation assigned for 
> their intended domains. The distinction between input and output terms 
> is made in order to guarantee that whenever all input values of one of 
> the given binding patterns are bound to concrete values, the fixed 
> interpretation only allows a finite number of bindings for the output 
> values such that the predicate evaluates to true, and those finite set 
> of bindings which can be computed by an external evaluation oracle.
> 
> If we agree to add something like binding patterns to DTB, I could start 
> to "collect" the possible binding patterns for the DTB predicates.
> 
> Side remark: note that external functions don't need binding patterns 
> (obviously all parameters are 'in' and the only 'out' is the result.)
> 
> Axel Polleres wrote:
> > Two pointers here... the notion of strong safety in hex-programs [1,2] 
> > and Topor's considerations on  safe database queries with arithmetics 
> > [3] (cudos jos for the latter one)
> > 
> > 
> > 1. R. Schindlauer. Answer-Set Programming for the Semantic Web. PhD 
> > thesis, Vienna University of Technology, Dec. 2006.
> > http://www.kr.tuwien.ac.at/staff/roman/papers/thesis.pdf
> > 
> > 2.  Thomas Eiter, Giovambattista Ianni, Roman Schindlauer, and Hans 
> > Tompits. Effective Integration of Declarative Rules with External 
> > Evaluations for Semantic Web Reasoning. In York Sure and John Domingue, 
> > editors, Proceedings of the 3rd European Conference on Semantic Web 
> > (ESWC 2006), Budva, Montenegro, number 4011 in Lecture Notes in Computer 
> > Science (LNCS), pages 273-287. Springer, June 2006.
> > http://www.springerlink.com/content/f0x23wx142141v44/
> > 
> > 3. R. Topor. Safe database queries with arithmetic relations (1991)
> > Proc. 14th Australian Computer Science Conf 
> > http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.48.4845
> > 
> > 
> 
>

Received on Tuesday, 12 August 2008 22:35:07 UTC