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Hacking the semantic linked data web

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Month: July, 2005

SPARQL RDF Query Language Reference update v1.7

I’ve updated my SPARQL RDF Query Language Reference to match the recently released SPARQL Query Language 21 July 2005 Working Draft.

While doing that I have also got a list of some of the more visible (syntax) changes, which is are as follows (this may not be a complete list):

  • Blank nodes are allowed in any part of a triple pattern and act as variables that cannot be SELECTed, that is, cannot be returned in variable bindings results.
  • FILTER expressions now normally take ()s except where it isn’t ambiguous, such as when any of the builtin functions such as REGEX are used at the root of the expression e.g. FILTER REGEX(...)

  • The FROM URI keyword is now repeatable which adds more triples to the background graph, doing an RDF merge. Any boundaries between loaded graphs are lost. If you want those, use FROM NAMED.
  • ASC and DESC in ORDER BY now use ()s not []s.
  • ORDER BY can now explicitly take expressions and extension functions without the need for ASC (default) or DESC.
  • The arguments of REGEX are now expressions not constant literals
  • The pattern syntax of REGEX is from XQuery 1.0 / XPath 2.0 Functions and Operators modifying it from XML Schema Datatypes Regular Expressions and similar to a Perl subset.

ObPlug: You can try most of this out in my Rasqal RDF query demo which is updated for the syntax, but the engine doesn’t do all the language yet.

SPARQL Query Language for RDF Last Call Working Draft 21 July 2005

The RDF Data Access Working Group (DAWG) has just published SPARQL Query Language for RDF Last Call Working Draft 21 July 2005 edited by Eric Prud’hommeaux, W3C and Andy Seaborne, Hewlett-Packard Laboratories, Bristol.

Yes, last call. That is, the working group thinks it is done. There are many changes and improvements ranging from text and formalism polishing, some syntax parts and some more substantial changes. SPARQLing drinks all round!

A good news day

A good news day: London beats Paris to 2012 [Olympic] Games and [European Union] Software patent bill thrown out.

Eric Raymond: We Don’t Need the GPL Anymore

Eric Raymond: “We Don’t Need the GPL Anymore” (ONLamp.com)