On 02/09/13 16:34, Charles Li wrote
Thanks Andy!
I managed to narrow down to the following SPAQL query issue (the
model was in TDB loaded from file "C:/temp/myrdf.xml". Jena 2.10.1)
When I run the following query:
select ?s ?p ?o WHERE { <file:///C:/temp/myrdf.xml#ROOT> ?p ?o
. }
I was able to get the correct triples (the logical tree structure
root is modeled in the RDF file with a node whose RdfId is literally
"ROOT") .
However, when I plug in the RdfId with the following query:
select ?s ?p ?o WHERE { <file:///C:/temp/myrdf.xml#
_{27900499-0D9D-4287-8F4D-E4C13BCB3C8D}> ?p ?o . }
I got an error:
Encountered " "<" "< "" ......
{ and } are illegal in IRIs. Ideally, your data would not use them.
You may run into other problems if you continue to use bad IRIs.
You probably got a warning when loading data.
So I think it may be due to the special characters in the RdfID, and
I tried the following query:
select ?s ?p ?o WHERE {
URI(ENCODE_FOR_URI("file:///C:/temp/myrdf.xml#_{27900499-0D9D-4287-8F4D-E4C13BCB3C8D}"))
?p ?o .
}
Encoding is not escaping.
If you encode { as %7B then the characters in the IRI are %-7-B, it's
not a way like \n to get the raw character into IRI.
You can try: CONTAINS(STR(...)) as you had before but on the correct
variable now we've established it is in the subject position.
SELECT * {
?s ?p ?o
FILTER( CONTAINS(STR(?s), "27900499-0D9D-4287-8F4D-E4C13BCB3C8D")
}
or
FILTER( STR(?s) =
"file:///C:/temp/myrdf.xml#_{0E43691F-0B64-42AF-AFCF-19BCC28ACBA3}")
This is not a fast query - it's a scan of the entire database - but you
could use it to convert your data using SPARQL Update.
You can also use initial bindings (see QueryExecutionFactory) on a query
to inject values after the parse stage.
But still syntax error.
which is unrelated to the URI issue. You need to look at the spec or a
book like "Learning SPARQL" or one of the many online introductions.
Guessing at syntax is going to take you a long time.
How should I compose the SPARQL query string to specify the RdfID in
place correctly?
Thanks a lot!
- Charles
Andy
