On 02/06/15 09:20, Charles Abela wrote:
Hi,
I'm working with a dynamic environment and have instances with some of
their properties that get updated with time, such as the rank property below
<http://jena.apache.org/documentation/tdb/tdb_transactions.html>
a <http://test.org/vocabulary/actions/Node> ;
<http://test.org/vocabulary/actions/id>
92 ;
<http://test.org/vocabulary/actions/rank>
"2.181"^^<http://www.w3.org/2001/XMLSchema#double> ,
"1.672"^^<http://www.w3.org/2001/XMLSchema#double> , "0.233"^^<
http://www.w3.org/2001/XMLSchema#double> , "0.466"^^<
http://www.w3.org/2001/XMLSchema#double> , "0.274"^^<
http://www.w3.org/2001/XMLSchema#double> , "0.543"^^<
http://www.w3.org/2001/XMLSchema#double> , "0.86"^^<
http://www.w3.org/2001/XMLSchema#double> , "1.234"^^<
http://www.w3.org/2001/XMLSchema#double> .
A double can be written shorthand as 1.234e0 -- the "e0" indicates a
double and wil be part of the lexical form.
@prefix : <http://test.org/vocabulary/actions/> .
@prefix text: <http://jena.apache.org/text#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix actions: <http://test.org/vocabulary/actions/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
<http://jena.apache.org/documentation/tdb/tdb_transactions.html>
rdf:type actions:Node ;
actions:id 92 ;
actions:rank "2.181"^^xsd:double ;
actions:rank "1.672"^^xsd:double ;
actions:rank "0.233"^^xsd:double ;
actions:rank "0.466"^^xsd:double ;
actions:rank "0.274"^^xsd:double ;
actions:rank "0.543"^^xsd:double ;
actions:rank "0.86"^^xsd:double ;
actions:rank "1.234"^^xsd:double .
From the excerpt it can be seen that multiple rank values are being added.
I'm using sparql's combination of delete/insert to delete the current value
and add the updated one, as follows:
String pre = StrUtils.strjoinNL
(" PREFIX : <http://test.org/vocabulary/actions/>"
Not that it wil have any effect, you have the same namespace twice :
PREFIX : <http://test.org/vocabulary/actions/>
PREFIX actions: <http://test.org/vocabulary/actions/>
, "PREFIX text: <http://jena.apache.org/text#>"
, "PREFIX rdfs: <
http://www.w3.org/2000/01/rdf-schema#>"
,"PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>"
," PREFIX actions: <
http://test.org/vocabulary/actions/>"
,"PREFIX rdf: <
http://www.w3.org/1999/02/22-rdf-syntax-ns#>") ;
String prop = StrUtils.strjoinNL(
node,
What's the string 'node'?
" actions:rank ?rank . ");
dataset.begin(ReadWrite.WRITE) ;
This is TDB right?
String dq = StrUtils.strjoinNL
(
"DELETE { ",
prop, " }",
"INSERT {", data, "}",
What's data?
"WHERE { ",
prop," }"
);
Looks sort of OK. Something readable would be nice.
Printing the update to check is good for checkign things are happenign
as expected:
try {
UpdateRequest update = UpdateFactory.create(pre+"\n"+dq);
System.out.println(update) ;
GraphStore graphStore = GraphStoreFactory.create(dataset);
UpdateAction.execute(update,graphStore);
dataset.commit();
}catch(Exception ex){
ex.printStackTrace();
}finally { dataset.end() ; }
any ideas as to why the values are not being deleted?
Possibly node is wrong.
Does data get inserted?
Is teh data in the
Personally, I'd write:
DELETE WHERE { ... } ;
INSERT DATA { ... }
but that's a style thing.
Andy
thanks in advance.
