Posted in Semantic Web, Veudas on Sep 23rd, 2004 3 Comments »
Claire’s out tonight, so another evening spent on bulk rdf importing. Have managed to get the original 120705 statement dataset import down to 77.6 seconds - that’s ~1500 triples a second!
The extra speed was mainly due to removing the need for database URI to id lookups by taking an in-memory copy of the hashes table. […]
Posted in Semantic Web, Veudas on Sep 22nd, 2004 3 Comments »
Spent the evening working on bulk assert speed for my ifp smushing store. Managed to get a 120000 statement import down from 410 seconds to 109 seconds - that’s over 1000 triples per second. Pretty good considering the rdflib rdf/xml parsing takes 59 seconds on its own - I wonder how fast this would be […]
Posted in Semantic Web on Sep 11th, 2004 No Comments »
At work in our team we’re just hitting the merging-schemas problem.
We have an alerting system that uses rdf to describe the alert schedules for different types of event. It describes people and groups they belong to, in addition to their shift rotas etc..
On discovery of an event (e.g. system failure), the system consults the rdf […]
Posted in Semantic Web, Veudas on Sep 11th, 2004 1 Comment »
One of the things I’ve found when dealing with IFP merged data is that you get lots of URIs for the same logical resource.
A good example of this is foaf:Person ‘Dan Brickley’, who is mentioned in lots of peoples foaf files. Because Dan doesnt attribute a URI to himself (and why should he?), quite […]
Posted in Semantic Web, Veudas on Sep 10th, 2004 No Comments »
One of the reasons I need graphs in my ifpstore is that at work I have an application that needs to ensure it is getting its security information from the right source. It uses a store aggregated from multiple sources for its data, and so without graph-matching, any of the other sources could theoretically add […]
Posted in Semantic Web, Veudas on Sep 10th, 2004 No Comments »
Have implemented a basic ‘parser’ using dodgy regexes to split up the components of the query. It supports SOURCE and OPTIONAL, and inlines the constraints with the patterns. Works reasonably well if you stick to the basic format. Hopefully I’ll get round to uploading a demo later today.
Have also added graph management support to […]
Posted in Veudas on Sep 9th, 2004 No Comments »
I think I’m going to bundle my new store as part of my veudas project. It saves me having to start up a new sf project, and currently veudas is pretty tied to the ifpstore’s features (although theoretically you could plug in a different store with the same features).
Posted in Semantic Web, Veudas on Sep 8th, 2004 No Comments »
Currently my smushing-store design doesnt handle unsmushing. This isn’t a big problem for my needs currently, but conversations with Steve Harris indicated that it’s something required quite frequently by his customers.
Given that its not a common thing for me, I need a solution that doesnt affect query speed (e.g. so don’t want to use a […]
Posted in Semantic Web, Veudas on Sep 7th, 2004 1 Comment »
My IFP store design is a copy of the 3store design, but using 32bit ids instead of hashes in the triples table. This enables a single resource to have multiple URIs, which makes IFP smushing much simpler.
ifpstore currently uses 3 tables:
triples table:
- subject 32bit int
- predicate 32bit int
- object […]
Posted in Semantic Web on Sep 6th, 2004 No Comments »
A college at work pointed me at this interesting paper about getting meaning from unstructured data using LSI.
Posted in Semantic Web on Sep 4th, 2004 No Comments »
Have been writing an rdfstore in python based on Steve Harris’ excellent 3store. It is designed to handle IFPs efficiently, by replacing all the hashes in 3store with ids. These then link to a URI table enabling a 1-many resource to URI mapping.
Posted in General on Sep 1st, 2004 1 Comment »
I got married on 14th August to the lovely Claire Beckett. My mum has put some photos of the happy event on her website.
