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<DIV><SPAN class=285082422-11012007><FONT face=Arial size=2>I am trying to
implement a SPARQL endpoint webservice to a Redland database. <SPAN
class=285082422-11012007><FONT face=Arial size=2>When I do a query that finds no
results, the stringification of the query results is NULL (undef in Perl).
</FONT></SPAN>My understanding of the required XML output(<A
href="http://www.w3.org/TR/rdf-sparql-XMLres/">http://www.w3.org/TR/rdf-sparql-XMLres/</A>)
for the results of an empty (but not malformed or otherwise errant) query should
list the <head> section of selected variables and an empty <results>
element.</FONT></SPAN></DIV>
<DIV><SPAN class=285082422-11012007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=285082422-11012007><FONT face=Arial size=2>My simple SELECT *
WHERE { ?s ?p ?o } query isn't getting any errors when I put some data in the
database, but when there is no data (or when the WHERE clause doesn't match any
data I get this bogus string, with no error or warning from
Redland.</FONT></SPAN></DIV>
<DIV><SPAN class=285082422-11012007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=285082422-11012007><FONT face=Arial size=2>I am using Redland v
1.0.4 with Rasqal 0.9.13.</FONT></SPAN></DIV></BODY></HTML>