Re: How general is Owlready2?

Posted by Jiba on
URL: http://owlready.306.s1.nabble.com/How-general-is-Owlready2-tp2531p2541.html

Hi,

Owlready2 can use any ontology in any domain. It includes some advanced functionalties that were inspired by the problem I encountered with biomedical ontologies. However, these functionalities might still be useful outside medicine, and they are optional -- you can not use them at all if they do not match your need.

Owlready2 has been largely used outside the medical domains, e.g. in particle physics, material science, aeronotics, home automation, etc.

Regarding SPARQL, Owlready has two options: RDFlib (fair support of SPARQL but slow) and the Owlready native engine (much faster but still very new and does not support some complex query). But options are able to perform simple queries such as listing the individuals of a class (without or with subclasses).

The native SPARQL engine translates the query in SQL, and thus allows performances similar to SQL. It supports:

* SELECT, INSERT and DELETE queries
* UNION, OPTIONAL, FILTER, BIND, FILTER EXISTS, FILTER NOT EXISTS
* SELECT sub queries
* All SPARQL functions and aggregation functions
* Blank nodes notations with square bracket, e.g. '[ a XXX]'
* Parameters in queries (i.e. '??')
* Property path expressions, e.g. 'a/rdfs:subClassOf*',  excepted those listed below

But the following are not supported:
* SERVICE (Federated queries)
* GRAPH, FROM, FROM NAMED keywords
* VALUES in SELECT queries
* MINUS
* Property path expressions with parentheses of the following forms:
  - nested repeats, e.g. (a/p*)*
  - sequence nested inside a repeat, e.g. (p1/p2)*
  - negative property set nested inside a repeat, e.g. (!(p1 | p2))*
  i.e. repeats cannot contain other repeats, sequences and negative property sets.

Could you send me an example of SPARQL query that raises a Lexing error, please ?

Jiba