Lost BoyA journal of no fixed aims or direction by Leigh Dodds. If you see him wandering, point him in the direction of home.Twinkle on code.google.com- March 11, 2008 I've created a Google Code project for Twinkle. It's called twinkle-sparql-tools. If you're a Java developer andor a user of the tool and are interesting in contributing code then drop me a mail and I'll set up you up with source access....http://www.ldodds.com/blog/archives/000328.html Set Algebra For Updating a Triple Store- March 11, 2008 Lets assume we have a stored graph Gstore. Also that we have been given another graph of incoming data Gin that contains some modifications to a specific sub-graph. Lets also assume that we have a function view() that can extract the "equivalent" sub-graph (i.e. equivalent view) of the original data. In pseudo code to apply these updates we do the following: Gview = view(Gstore) Gdelete = Gview - Gin Ginsert = Gin - Gview Gstore' = Gstore.remove(Gdelete).add(Ginsert) Job done. The...http://www.ldodds.com/blog/archives/000327.html Graph Shape Sorting- March 10, 2008 On Sunday I posted about how constrained views of RDF can be useful in order to document the inputs into an application, validate those inputs, and also manage updates via application of set algebra. I explored the idea that a system may support many such views or "document types" without blessing any as the primary view of the data. And, importantly, that this approach doesn't ultimately constrain the range of data that you can put into a triple store. It just occured to me that...http://www.ldodds.com/blog/archives/000326.html Modelling Statistical Publications: Some Notes- March 10, 2008 Lee Feigenbaum has put together a really nice posting discussing different ways of modelling statistical data using RDF. I wanted to contribute to that discussion and add in a few comments about how I've been modelling some of the OECD's statistical publications using RDF. Note the emphasis: what I've been doing is capturing metadata about individual statistical tables and graphs, their association with specific publications, their metadata, etc. I've not attempted to capture the detail of the..http://www.ldodds.com/blog/archives/000325.html Documents Types in RDF- March 9, 2008 The notion of a "document" and a "document type" are core concepts in XML. The specification includes a precise description of document, what it means for a document to be well-formed, valid, and so on. Even if you're not using a DTD or XML schema, and are just using XML as a syntax for exchanging structured or semi-structured data, the concept of document is still a useful one. For example a document has a clear boundary and content, and so there is a limited scope for the..http://www.ldodds.com/blog/archives/000324.html Oxford SWIG Talks: Twinkle & SPARQL Query Forms- March 7, 2008 I finally found time to attend one of the Oxford SWIG sessions last night and had a thoroughly enjoyable time. I gave a couple of presentations which I've posted to slideshare, and which I'll embed below. The first was a general introduction and mini-demonstration of Twinkle. I gave a basic overview of the key features and showed how the configuration drives the user interface: View Upload your own The second talk as about the different SPARQL query forms. I started by asking the question...http://www.ldodds.com/blog/archives/000323.html |