Martin, It's roll of dice. SPARQL comparison of RDF literals of different types is not specified, the exception is comparison of RDF literals of different numeric types.
I intend to improve it, well, some day, but I should warn that it will be in some distant future. Please cast values to some common type. Best Regards, Ivan Mikhailov OpenLink Software http://virtuoso.openlinksw.com On Tue, 2011-06-21 at 17:39 +0200, Martin Gerlach wrote: > Hi, > > is there any documentation on which date/time types can be safely used > in comparisons? > > I noticed that xsd:gYear and xsd:date do not work: > > SELECT > ('2007'^^xsd:gYear < '2007-01-01'^^xsd:date) > ('2007'^^xsd:gYear <= '2007-01-01'^^xsd:date) > ('2007'^^xsd:gYear > '2007-01-01'^^xsd:date) > ('2007'^^xsd:gYear >= '2007-01-01'^^xsd:date) > ('2006'^^xsd:gYear < '2007-01-01'^^xsd:date) > ('2006'^^xsd:gYear <= '2007-01-01'^^xsd:date) > ('2006'^^xsd:gYear > '2007-01-01'^^xsd:date) > ('2006'^^xsd:gYear >= '2007-01-01'^^xsd:date) > ('2008'^^xsd:gYear < '2007-01-01'^^xsd:date) > ('2008'^^xsd:gYear <= '2007-01-01'^^xsd:date) > ('2008'^^xsd:gYear > '2007-01-01'^^xsd:date) > ('2008'^^xsd:gYear >= '2007-01-01'^^xsd:date) > WHERE{ > } > > shows that all comparisons using < or > yield 0, whereas all > comparisons using <= or >= yield 1 regardless of the actual literal > values. (Same if the lhs has xsd:date and the rhs xsd:gYear) > > Thanks, > Martin > > -- > > ______________________________________________________________________ > > Martin Gerlach > Senior Softwareentwickler > Research > > Neofonie GmbH > Robert-Koch-Platz 4 > 10115 Berlin > > T +49.30 24627 413 > F +49.30 24627 120 > [email protected] > http://www.neofonie.de > > Handelsregister > Berlin-Charlottenburg: HRB 67460 > > Geschäftsführung > Thomas Kitlitschko > Dr. Mario Lenz > > > ------------------------------------------------------------------------------ > EditLive Enterprise is the world's most technically advanced content > authoring tool. Experience the power of Track Changes, Inline Image > Editing and ensure content is compliant with Accessibility Checking. > http://p.sf.net/sfu/ephox-dev2dev > _______________________________________________ Virtuoso-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/virtuoso-users
