Re: deductive databases in postgreSQL

Carlos Gonzalez-Cadenas escreveu:
> We're looking for a deductive database for our application. Oracle, in
> the 11g version, has extended its RDBMS with deductive capabilities,
> supporting a subset of OWL-DL[1]. They are able to load an ontology,
> perform the inferences, dump the inferred info in the database and after
> that answer queries with the asserted plus the inferred info.
>
> We would like to have similar functionalities in PostgreSQL. Do you know
> if there's someone working on that or if there are plans to support it
> soon?. If not, what do you think is the best and most efficient way of
> implementing it?
>
No one that I know of. Well, it is a long road. The addition of a data type
xml is recent (8.3). We lack a set of features like indexing, a new data
structure (?), XQuery, XPath improvement and, so on [1]. Don't expect much of
these TODO items completed before the next two releases (unless you want to
take a stab).
After all of these basic infrastructure, we need a language (SPARQL?) and an
inference engine -- this is a big task AFAICT. At this point, don't know if
hackers will agree in adding such a big feature in core that is not SQL
standard (aka SQL/XML) but maybe it could be an external module.

[1] http://wiki.postgresql.org/wiki/XML_Todo

--
Euler Taveira de Oliveira
http://www.timbira.com/