Orri Erling's Weblog

• Significant rewrite of database engine resulting in 50%-100% improvement on single CPU and in some cases up to 300% on multiprocessor CPUs by decreasing resource-contention between threads and other optimizations.
• Radical expansion of RDF support including

• In-built middleware (called the Sponger) for transforming non-RDF into RDF "on the fly" (e.g. producing Triples from Microformats, REST-style Web Services, and (X)HTML etc.)
• Full Text Indexing of Literal Objects in Triple Patterns (via Filter or magic bif:contains predicate applied to Literal Objects)
• Basic Inferencing (Subclass and Subproperty Support)
• SPARQL Aggregate Functions
• SPARQL Update Language Support (Updates, Inserts, Deletions in SPARQL)
• Improved Support of XML Schema Type System (including the use of XML Schema Complex Types as Objects of bif:xcontains predicate)
• Enhancements to the in-built SPARQL to SQL Compiler's Cost Optimizer
• Performance Optimizations to RDF VIEWs (SQL to RDF Mapping)

• Various bug-fixes

• Home Page: http://virtuoso.openlinksw.com/wiki/main/
• Download Page: http://virtuoso.openlinksw.com/wiki/main/Main/VOSDownload

• Home Page: http://virtuoso.openlinksw.com/wiki/main/Main/OdsIndex
• SPARQL Usage Examples (re. SIOC, FOAF, AtomOWL, SKOS): http://virtuoso.openlinksw.com/wiki/main/Main/ODSSIOCRef
• Interactive SPARQL Demo: http://demo.openlinksw.com/isparql/

• Project Page: http://sourceforge.net/projects/oat
• Live Demonstration: http://demo.openlinksw.com/DAV/JS/oat/index.html

Technorati Tags: database, databases, open-source, OpenLink, SPARQL, RDBMS, RDF, semantic web, Semantic Web, virtuoso

We have been extensively working on virtual database refinements.  There aremany SQL cost model adjustments to better model  distributed queries and wenow support direct access to Oracle and Informix statistics system tables.Thus, when you attach  a table from one or the other, you automatically getup to date statistics.  This helps Virtuoso optimize distributed  queries.Also the documentation is updated as concerns these, with a new section ondistributed query optimization.

On the applications side, we have been keeping up with the SIOC RDF ontologydevelopments.  All ODS applications now make  their data available as SIOCgraphs for download and SPARQL query access.

What is most exciting however is our advance in mapping relational data intoRDF.  We now have a mapping language that makes  arbitrary legacy data in Virtuoso or elsewhere in the relational world RDF queriable.  We will putout a white paper on  this in a few days.

Also we have some innovations in mind for optimizing the physical storage ofRDF triples.  We keep experimenting, now with  our sights set to the highend of triple storage, towards billion triple data sets.  We areexperimenting with a new more space efficient index structure  for betterworking set behavior.  Next week will yield the first results.