Re: [Rdfapi-php-interest] Scalability and performance

[<au...@in...>]

We have used Powl with RAP as a basis with quite large knowledge bases 
(0.5M triples). My experience is, that performance is determined largely 
by the underlying database, if you try to encode as much as possible in 
SQL queries. In Powl we have gone this way and enhanced RAP with quite a 
lot of API functions triggering quite complex SQL queries. For sure it 
would be better to use SPARQL instead, but in the time we started to 
work on Powl SPARQL was not yet available and still I have the 
impression, there are lots of crucial features missing (e.g. aggregations).
 From my point of view it would be good if someone could integrate a 
SPARQL-SQL query rewriting in to RAP (e.g. port Benjamins work). We are 
actually working on an intelligent caching strategy allowing for 
selective cache object invalidation on updates and their implementation 
for RAP.

Cheers,

Sören