[Rdfapi-php-interest] RAP DB

[Gunnar A. G. <ggr...@cs...>]

Hi all,

Good idea to setup a mailing-list chris!

This might be a bit early, as there might not be anyone else than me and 
chris subscribed yet, but others can always check the archive.

Here the other day I needed to put a 120mb rdf/xml file into a RAP DB, I 
tried using the db-tool and uploading it, but on my P4 with 1gb of 
memory it used 1.8gb of memory, froze the whole machine and was still 
showing no sign of connecting to the DB after 30 minutes, so I stopped it.

Instead admitted that maybe PHP isn't right for everything and wrote a 
java program to insert into mysql DB in RAPDB format. The program is 
attached, and currently requires jena2, Java getopt 
(http://www.urbanophile.com/arenn/hacking/download.html) and probably 
java 1.5.

With this you can for example do:

java RAPDBInsert -m "http://example.org" -h trogon -u ggrimnes -p **** 
-d rdf ~/public_html/foaf.rdf

This worked like a dream, and I've now got a RAP DB with 1579160 (1.5M!) 
triples. Normal operations like $model->find($res,$DC_title,null) are 
quick, but anything that requires getting the whole model into memory 
(f.x. regex finds) breaks everything. Even getting the size of the model 
takes ~=15s, but with some care it's fully usable!

Anyway, hope this might be useful to someone else.

- Gunnar


-- 
Gunnar AAstrand Grimnes
-----------------------
Room 312, Computing Science Dept.
University of Aberdeen
Aberdeen
AB24 3UE

Mobile: (+44) (0) 7950 251379

Email: ggr...@cs...
WWW: http://www.csd.abdn.ac.uk/~ggrimnes