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Posted to users@jena.apache.org by George News <ge...@gmx.net> on 2017/02/27 18:18:59 UTC
SPARQL with UNION returning TDBTransactionException
Hi,
I have a SELECT SPARQL query similar to the one below:
|PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs:
<http://www.w3.org/2000/01/rdf-schema#> SELECT (count(distinct ?o) as
?count_o) (count(distinct ?device) as ?count_devices) WHERE { {?o
rdf:type/rdfs:subClassOf CLASS1 .} UNION {?device
rdf:type/rdfs:subClassOf CLASS2 .} } |
If I execute it as it is, I get
|org.apache.jena.tdb.transaction.TDBTransactionException: Not in a
transaction |
However if I execute it like
|PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs:
<http://www.w3.org/2000/01/rdf-schema#> SELECT (count(distinct ?o) as
?count_observations) WHERE { {?o rdf:type/rdfs:subClassOf CLASS1 .} } |
everything is working ok. It doesn\u2019t matter if I use one or the other
part of the union, as it works ok independently but not together.
Any idea? Any help is more than welcome.
Find below part of the code:
|public SparqlResult executeSparql(String sparql) throws
SparqlExecutionException { String queryString = sparql; Query query =
QueryFactory.create(queryString); dataset.begin(ReadWrite.READ); try {
QueryExecution qExec = QueryExecutionFactory.create(query, getModel());
// System.out.println(qExec.getQuery().serialize()); //
System.out.println(qExec.getQuery().toString()); SparqlResult result; if
(query.isSelectType()) { result = new SparqlResult(qExec.execSelect(),
qExec); } else if (query.isDescribeType()) { result = new
SparqlResult(qExec.execDescribe(), qExec); } else if (query.isAskType())
{ result = new SparqlResult(qExec.execAsk(), qExec); } else if
(query.isConstructType()) { result = new
SparqlResult(qExec.execConstruct(), qExec); } else { throw new
SparqlExecutionException("Unsupported query type: " +
query.getQueryType()); } return result; } finally { dataset.end(); }
private Map<String, Integer> getSummaryStatistics() { String queryString
= "THE_ONE"; Map<String, Integer> statistics = new HashMap<>();
GlobalTripleStore gts = new GlobalTripleStore(); try (SparqlResult
result = gts.executeSparql(queryString)) { ResultSet resultSet =
(ResultSet) result.getResult(); while (resultSet.hasNext()) {
QuerySolution sol = resultSet.next(); int devices =
sol.get("count_devices").asLiteral().getInt(); int observations
=sol.get("count_o").asLiteral().getInt(); statistics.put("devices",
resources); statistics.put("o", observations); } } catch
(SparqlExecutionException e) { // TODO Auto-generated catch block
e.printStackTrace(); } return statistics; } |
\u200b
Re: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
More information... I have also noticed that if I don't close the
transaction (dataset.end()) it works. But, are the transactions garbage
collected?
What is the different between using UNION and not using it internally
for Jena? the other option is using RewindableResultSet, which somehow I
want to avoid. But if this is the solution, I will go though all my
ResultSets twice, one for retrieval (Rewindable creation) and another
for analysing the data.
On 27/02/2017 19:23, George News wrote:
> Sorry I forgot to include the full exception
>
> Caused by: org.apache.jena.tdb.transaction.TDBTransactionException: Not in a transaction
> at org.apache.jena.tdb.transaction.DatasetGraphTransaction.get(DatasetGraphTransaction.java:117)
> at org.apache.jena.tdb.transaction.DatasetGraphTransaction.get(DatasetGraphTransaction.java:50)
> at org.apache.jena.sparql.core.DatasetGraphWrapper.getR(DatasetGraphWrapper.java:61)
> at org.apache.jena.sparql.core.DatasetGraphWrapper.find(DatasetGraphWrapper.java:146)
> at org.apache.jena.sparql.core.GraphView.graphBaseFind(GraphView.java:121)
> at org.apache.jena.graph.impl.GraphBase.find(GraphBase.java:255)
> at org.apache.jena.sparql.path.eval.PathEngine.graphFind2(PathEngine.java:205)
> at org.apache.jena.sparql.path.eval.PathEngine.graphFind(PathEngine.java:189)
> at org.apache.jena.sparql.path.eval.PathEngine.graphFind(PathEngine.java:171)
> at org.apache.jena.sparql.path.eval.PathEngine.doOne(PathEngine.java:92)
> at org.apache.jena.sparql.path.eval.PathEvaluator.visit(PathEvaluator.java:57)
> at org.apache.jena.sparql.path.P_Link.visit(P_Link.java:37)
> at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:68)
> at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:74)
> at org.apache.jena.sparql.path.eval.PathEngine.eval(PathEngine.java:75)
> at org.apache.jena.sparql.path.eval.PathEngineSPARQL.ALP_1(PathEngineSPARQL.java:119)
> at org.apache.jena.sparql.path.eval.PathEngineSPARQL.doZeroOrMore(PathEngineSPARQL.java:92)
> at org.apache.jena.sparql.path.eval.PathEvaluator.visit(PathEvaluator.java:115)
> at org.apache.jena.sparql.path.P_ZeroOrMore1.visit(P_ZeroOrMore1.java:43)
> at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:68)
> at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:74)
> at org.apache.jena.sparql.path.eval.PathEval.eval(PathEval.java:37)
> at org.apache.jena.sparql.path.PathLib.evalGroundedPath(PathLib.java:166)
> at org.apache.jena.sparql.path.PathLib.execTriplePath(PathLib.java:133)
> at org.apache.jena.sparql.path.PathLib.execTriplePath(PathLib.java:108)
> at org.apache.jena.sparql.engine.iterator.QueryIterPath.nextStage(QueryIterPath.java:47)
> at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.makeNextStage(QueryIterRepeatApply.java:108)
> at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:65)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.atlas.iterator.Iter$2.hasNext(Iter.java:265)
> at org.apache.jena.atlas.iterator.RepeatApplyIterator.hasNext(RepeatApplyIterator.java:45)
> at org.apache.jena.tdb.solver.SolverLib$IterAbortable.hasNext(SolverLib.java:195)
> at org.apache.jena.atlas.iterator.Iter$2.hasNext(Iter.java:265)
> at org.apache.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(QueryIterPlainWrapper.java:53)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.makeNextStage(QueryIterRepeatApply.java:101)
> at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:65)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.makeNextStage(QueryIterRepeatApply.java:101)
> at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:65)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIterGroup$1.initializeIterator(QueryIterGroup.java:86)
> at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.init(IteratorDelayedInitialization.java:40)
> at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.hasNext(IteratorDelayedInitialization.java:50)
> at org.apache.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(QueryIterPlainWrapper.java:53)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIterProcessBinding.hasNextBinding(QueryIterProcessBinding.java:66)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIterConvert.hasNextBinding(QueryIterConvert.java:58)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIterDistinct.getInputNextUnseen(QueryIterDistinct.java:104)
> at org.apache.jena.sparql.engine.iterator.QueryIterDistinct.hasNextBinding(QueryIterDistinct.java:70)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at java.util.Iterator.forEachRemaining(Iterator.java:115)
> at org.apache.jena.atlas.data.DataBag.addAll(DataBag.java:94)
> at org.apache.jena.sparql.engine.iterator.QueryIterSort$SortedBindingIterator.initializeIterator(QueryIterSort.java:84)
> at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.init(IteratorDelayedInitialization.java:40)
> at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.hasNext(IteratorDelayedInitialization.java:50)
> at org.apache.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(QueryIterPlainWrapper.java:53)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:39)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:39)
> at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
> at org.apache.jena.sparql.engine.ResultSetStream.hasNext(ResultSetStream.java:74)
> at org.apache.jena.sparql.engine.ResultSetCheckCondition.hasNext(ResultSetCheckCondition.java:55)
>
>
>
>
> On 27/02/2017 19:18, George News wrote:
>> Hi,
>>
>> I have a SELECT SPARQL query similar to the one below:
>>
>> |PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs:
>> <http://www.w3.org/2000/01/rdf-schema#> SELECT (count(distinct ?o) as
>> ?count_o) (count(distinct ?device) as ?count_devices) WHERE { {?o
>> rdf:type/rdfs:subClassOf CLASS1 .} UNION {?device
>> rdf:type/rdfs:subClassOf CLASS2 .} } |
>>
>> If I execute it as it is, I get
>>
>> |org.apache.jena.tdb.transaction.TDBTransactionException: Not in a
>> transaction |
>>
>> However if I execute it like
>>
>> |PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs:
>> <http://www.w3.org/2000/01/rdf-schema#> SELECT (count(distinct ?o) as
>> ?count_observations) WHERE { {?o rdf:type/rdfs:subClassOf CLASS1 .} } |
>>
>> everything is working ok. It doesn\u2019t matter if I use one or the other
>> part of the union, as it works ok independently but not together.
>>
>> Any idea? Any help is more than welcome.
>>
>> Find below part of the code:
>>
>> |public SparqlResult executeSparql(String sparql) throws
>> SparqlExecutionException { String queryString = sparql; Query query =
>> QueryFactory.create(queryString); dataset.begin(ReadWrite.READ); try {
>> QueryExecution qExec = QueryExecutionFactory.create(query, getModel());
>> // System.out.println(qExec.getQuery().serialize()); //
>> System.out.println(qExec.getQuery().toString()); SparqlResult result; if
>> (query.isSelectType()) { result = new SparqlResult(qExec.execSelect(),
>> qExec); } else if (query.isDescribeType()) { result = new
>> SparqlResult(qExec.execDescribe(), qExec); } else if (query.isAskType())
>> { result = new SparqlResult(qExec.execAsk(), qExec); } else if
>> (query.isConstructType()) { result = new
>> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
>> SparqlExecutionException("Unsupported query type: " +
>> query.getQueryType()); } return result; } finally { dataset.end(); }
>> private Map<String, Integer> getSummaryStatistics() { String queryString
>> = "THE_ONE"; Map<String, Integer> statistics = new HashMap<>();
>> GlobalTripleStore gts = new GlobalTripleStore(); try (SparqlResult
>> result = gts.executeSparql(queryString)) { ResultSet resultSet =
>> (ResultSet) result.getResult(); while (resultSet.hasNext()) {
>> QuerySolution sol = resultSet.next(); int devices =
>> sol.get("count_devices").asLiteral().getInt(); int observations
>> =sol.get("count_o").asLiteral().getInt(); statistics.put("devices",
>> resources); statistics.put("o", observations); } } catch
>> (SparqlExecutionException e) { // TODO Auto-generated catch block
>> e.printStackTrace(); } return statistics; } |
>>
>> \u200b
>>
>>
>
Re: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
Sorry I forgot to include the full exception
Caused by: org.apache.jena.tdb.transaction.TDBTransactionException: Not in a transaction
at org.apache.jena.tdb.transaction.DatasetGraphTransaction.get(DatasetGraphTransaction.java:117)
at org.apache.jena.tdb.transaction.DatasetGraphTransaction.get(DatasetGraphTransaction.java:50)
at org.apache.jena.sparql.core.DatasetGraphWrapper.getR(DatasetGraphWrapper.java:61)
at org.apache.jena.sparql.core.DatasetGraphWrapper.find(DatasetGraphWrapper.java:146)
at org.apache.jena.sparql.core.GraphView.graphBaseFind(GraphView.java:121)
at org.apache.jena.graph.impl.GraphBase.find(GraphBase.java:255)
at org.apache.jena.sparql.path.eval.PathEngine.graphFind2(PathEngine.java:205)
at org.apache.jena.sparql.path.eval.PathEngine.graphFind(PathEngine.java:189)
at org.apache.jena.sparql.path.eval.PathEngine.graphFind(PathEngine.java:171)
at org.apache.jena.sparql.path.eval.PathEngine.doOne(PathEngine.java:92)
at org.apache.jena.sparql.path.eval.PathEvaluator.visit(PathEvaluator.java:57)
at org.apache.jena.sparql.path.P_Link.visit(P_Link.java:37)
at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:68)
at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:74)
at org.apache.jena.sparql.path.eval.PathEngine.eval(PathEngine.java:75)
at org.apache.jena.sparql.path.eval.PathEngineSPARQL.ALP_1(PathEngineSPARQL.java:119)
at org.apache.jena.sparql.path.eval.PathEngineSPARQL.doZeroOrMore(PathEngineSPARQL.java:92)
at org.apache.jena.sparql.path.eval.PathEvaluator.visit(PathEvaluator.java:115)
at org.apache.jena.sparql.path.P_ZeroOrMore1.visit(P_ZeroOrMore1.java:43)
at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:68)
at org.apache.jena.sparql.path.eval.PathEval.eval$(PathEval.java:74)
at org.apache.jena.sparql.path.eval.PathEval.eval(PathEval.java:37)
at org.apache.jena.sparql.path.PathLib.evalGroundedPath(PathLib.java:166)
at org.apache.jena.sparql.path.PathLib.execTriplePath(PathLib.java:133)
at org.apache.jena.sparql.path.PathLib.execTriplePath(PathLib.java:108)
at org.apache.jena.sparql.engine.iterator.QueryIterPath.nextStage(QueryIterPath.java:47)
at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.makeNextStage(QueryIterRepeatApply.java:108)
at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:65)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.atlas.iterator.Iter$2.hasNext(Iter.java:265)
at org.apache.jena.atlas.iterator.RepeatApplyIterator.hasNext(RepeatApplyIterator.java:45)
at org.apache.jena.tdb.solver.SolverLib$IterAbortable.hasNext(SolverLib.java:195)
at org.apache.jena.atlas.iterator.Iter$2.hasNext(Iter.java:265)
at org.apache.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(QueryIterPlainWrapper.java:53)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.makeNextStage(QueryIterRepeatApply.java:101)
at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:65)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.makeNextStage(QueryIterRepeatApply.java:101)
at org.apache.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:65)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIterGroup$1.initializeIterator(QueryIterGroup.java:86)
at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.init(IteratorDelayedInitialization.java:40)
at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.hasNext(IteratorDelayedInitialization.java:50)
at org.apache.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(QueryIterPlainWrapper.java:53)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIterProcessBinding.hasNextBinding(QueryIterProcessBinding.java:66)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIterConvert.hasNextBinding(QueryIterConvert.java:58)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIterDistinct.getInputNextUnseen(QueryIterDistinct.java:104)
at org.apache.jena.sparql.engine.iterator.QueryIterDistinct.hasNextBinding(QueryIterDistinct.java:70)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at java.util.Iterator.forEachRemaining(Iterator.java:115)
at org.apache.jena.atlas.data.DataBag.addAll(DataBag.java:94)
at org.apache.jena.sparql.engine.iterator.QueryIterSort$SortedBindingIterator.initializeIterator(QueryIterSort.java:84)
at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.init(IteratorDelayedInitialization.java:40)
at org.apache.jena.atlas.iterator.IteratorDelayedInitialization.hasNext(IteratorDelayedInitialization.java:50)
at org.apache.jena.sparql.engine.iterator.QueryIterPlainWrapper.hasNextBinding(QueryIterPlainWrapper.java:53)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:39)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:39)
at org.apache.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:114)
at org.apache.jena.sparql.engine.ResultSetStream.hasNext(ResultSetStream.java:74)
at org.apache.jena.sparql.engine.ResultSetCheckCondition.hasNext(ResultSetCheckCondition.java:55)
On 27/02/2017 19:18, George News wrote:
> Hi,
>
> I have a SELECT SPARQL query similar to the one below:
>
> |PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs:
> <http://www.w3.org/2000/01/rdf-schema#> SELECT (count(distinct ?o) as
> ?count_o) (count(distinct ?device) as ?count_devices) WHERE { {?o
> rdf:type/rdfs:subClassOf CLASS1 .} UNION {?device
> rdf:type/rdfs:subClassOf CLASS2 .} } |
>
> If I execute it as it is, I get
>
> |org.apache.jena.tdb.transaction.TDBTransactionException: Not in a
> transaction |
>
> However if I execute it like
>
> |PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs:
> <http://www.w3.org/2000/01/rdf-schema#> SELECT (count(distinct ?o) as
> ?count_observations) WHERE { {?o rdf:type/rdfs:subClassOf CLASS1 .} } |
>
> everything is working ok. It doesn\u2019t matter if I use one or the other
> part of the union, as it works ok independently but not together.
>
> Any idea? Any help is more than welcome.
>
> Find below part of the code:
>
> |public SparqlResult executeSparql(String sparql) throws
> SparqlExecutionException { String queryString = sparql; Query query =
> QueryFactory.create(queryString); dataset.begin(ReadWrite.READ); try {
> QueryExecution qExec = QueryExecutionFactory.create(query, getModel());
> // System.out.println(qExec.getQuery().serialize()); //
> System.out.println(qExec.getQuery().toString()); SparqlResult result; if
> (query.isSelectType()) { result = new SparqlResult(qExec.execSelect(),
> qExec); } else if (query.isDescribeType()) { result = new
> SparqlResult(qExec.execDescribe(), qExec); } else if (query.isAskType())
> { result = new SparqlResult(qExec.execAsk(), qExec); } else if
> (query.isConstructType()) { result = new
> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
> SparqlExecutionException("Unsupported query type: " +
> query.getQueryType()); } return result; } finally { dataset.end(); }
> private Map<String, Integer> getSummaryStatistics() { String queryString
> = "THE_ONE"; Map<String, Integer> statistics = new HashMap<>();
> GlobalTripleStore gts = new GlobalTripleStore(); try (SparqlResult
> result = gts.executeSparql(queryString)) { ResultSet resultSet =
> (ResultSet) result.getResult(); while (resultSet.hasNext()) {
> QuerySolution sol = resultSet.next(); int devices =
> sol.get("count_devices").asLiteral().getInt(); int observations
> =sol.get("count_o").asLiteral().getInt(); statistics.put("devices",
> resources); statistics.put("o", observations); } } catch
> (SparqlExecutionException e) { // TODO Auto-generated catch block
> e.printStackTrace(); } return statistics; } |
>
> \u200b
>
>
Re: Deleting the default graph from the TDB
Posted by Sandor Kopacsi <sa...@univie.ac.at>.
Thank you very much, that was the problem.
I did not change so far this default setting in the config file:
<#dataset> rdf:type tdb:DatasetTDB ;
tdb:location "/var/www/fuseki/tdb" ;
tdb:unionDefaultGraph true ;
I set it now to false (or better commented out), and now the DROP
DEFAULT SPARQL update works as expected.
Thanks again.
Best regards,
Sandor
Am 28.02.2017 um 19:10 schrieb A. Soroka:
> Do you have the default graph set up as the union graph?
>
> ---
> A. Soroka
> The University of Virginia Library
>
>> On Feb 28, 2017, at 12:21 PM, Sandor Kopacsi <sa...@univie.ac.at> wrote:
>>
>> Dear List-members!
>>
>> I would like to delete the default graph from TDB using the web interface of Fuseki, but for some reason it doesn't work.
>>
>> In the config file of Fuseki the serviceUpdate is allowed, and I can perform the CLEAR DEFAULT and DROP DEFAULT SPARQL updates successfully, but the default graph is still there, and contains triples.
>>
>> When I run Fuseki in the memory with the same setting and update above, I can simply delete the default graph.
>>
>> What is wrong?
>>
>> Thanks and best regards,
>> Sandor
>>
>> --
>>
>> Dr. Sandor Kopacsi
>> IT Software Designer
>>
>> Vienna University Computer Center
>>
--
Dr. Sandor Kopacsi
IT Software Designer
Vienna University Computer Center
Universittsstrae 7 (NIG)
A-1010 Vienna
Phone: +43-1-4277-14176
Mobile: +43-664-60277-14176
Re: Deleting the default graph from the TDB
Posted by "A. Soroka" <aj...@virginia.edu>.
Do you have the default graph set up as the union graph?
---
A. Soroka
The University of Virginia Library
> On Feb 28, 2017, at 12:21 PM, Sandor Kopacsi <sa...@univie.ac.at> wrote:
>
> Dear List-members!
>
> I would like to delete the default graph from TDB using the web interface of Fuseki, but for some reason it doesn't work.
>
> In the config file of Fuseki the serviceUpdate is allowed, and I can perform the CLEAR DEFAULT and DROP DEFAULT SPARQL updates successfully, but the default graph is still there, and contains triples.
>
> When I run Fuseki in the memory with the same setting and update above, I can simply delete the default graph.
>
> What is wrong?
>
> Thanks and best regards,
> Sandor
>
> --
>
> Dr. Sandor Kopacsi
> IT Software Designer
>
> Vienna University Computer Center
>
Deleting the default graph from the TDB
Posted by Sandor Kopacsi <sa...@univie.ac.at>.
Dear List-members!
I would like to delete the default graph from TDB using the web
interface of Fuseki, but for some reason it doesn't work.
In the config file of Fuseki the serviceUpdate is allowed, and I can
perform the CLEAR DEFAULT and DROP DEFAULT SPARQL updates successfully,
but the default graph is still there, and contains triples.
When I run Fuseki in the memory with the same setting and update above,
I can simply delete the default graph.
What is wrong?
Thanks and best regards,
Sandor
--
Dr. Sandor Kopacsi
IT Software Designer
Vienna University Computer Center
Re: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
On 28/02/2017 13:13, ajs6f@virginia.edu wrote:
> Try using a service like Github Gist.
I guess you say Gist for posting code. I can also use pastebin next time.
> Is it possible that only one of
> the legs of the query has results in it? Have you confirmed that
> _neither_ of the legs executed separately shows the problem?
Yes. As @Andy said UNION are executed separately. So the problem seems
to be that one branch works while the other no.
> ajs6f
>
>> On Feb 28, 2017, at 4:51 AM, Andy Seaborne <an...@apache.org>
>> wrote:
>>
>> What people on the list receive is:
>>
>> https://lists.apache.org/api/source.lua/8d17e5299cbbe585e7d45ff8ce156021162a9e16fe77818d8f7cff6c@%3Cusers.jena.apache.org%3E
>>
>>
>>
Looks like HTML to text conversion.
>>
>>> On 27/02/17 23:58, George News wrote: But the funny thing is that
>>> in both cases (with and without UNION) the code is the same. I
>>> know I close the transaction, but I don\u2019t understand why in one
>>> case it works and in the other no.
>>
>> Probably you close the transaction before the resultset is all
>> consumed.
>>
>> Some work is done on execSelect so internally, the use of the
>> dataset can finish early.
>>
>> UNION has two branches calculated separately.
>>
>> It depends on the real query.
>>
>> Andy
>>
>>>
>>> I would like to ask another thing: In a @requestscope is the
>>> reading transaction automatically close when finished the REST
>>> processing or is it mandatory to call dataset.end()?
>>>
>>> I don't knw why example code is unreadable. I have perfectly seen
>>> the code.
>>>
>>> Thanks a lot Jorge
>>>
>>> Sent from jlanza_lumia820
>>>
>>> From: Andy Seaborne Sent: martes, 28 de febrero de 2017 0:12 To:
>>> users@jena.apache.org Subject: Re: SPARQL with UNION returning
>>> TDBTransactionException
>>>
>>> Unreadable.
>>>
>>> -------------------------
>>>
>>> Probably you are passing the result stream out of the
>>> transaction.
>>>
>>> Reading a ResultSet requires reading the dataset and must be
>>> inside a transaction when the calls to hasNext/next are
>>> happening.
>>>
>>> Andy
>>>
>>>> On 27/02/17 18:18, George News wrote: |public SparqlResult
>>>> executeSparql(String sparql) throws SparqlExecutionException {
>>>> String queryString = sparql; Query query =
>>>> QueryFactory.create(queryString);
>>>> dataset.begin(ReadWrite.READ); try { QueryExecution qExec =
>>>> QueryExecutionFactory.create(query, getModel()); //
>>>> System.out.println(qExec.getQuery().serialize()); //
>>>> System.out.println(qExec.getQuery().toString()); SparqlResult
>>>> result; if (query.isSelectType()) { result = new
>>>> SparqlResult(qExec.execSelect(), qExec); } else if
>>>> (query.isDescribeType()) { result = new
>>>> SparqlResult(qExec.execDescribe(), qExec); } else if
>>>> (query.isAskType()) { result = new
>>>> SparqlResult(qExec.execAsk(), qExec); } else if
>>>> (query.isConstructType()) { result = new
>>>> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
>>>> SparqlExecutionException("Unsupported query type: " +
>>>> query.getQueryType()); } return result; } finally {
>>>> dataset.end(); } private Map<String, Integer>
>>>> getSummaryStatistics() { String queryString = "THE_ONE";
>>>> Map<String, Integer> statistics = new HashMap<>();
>>>> GlobalTripleStore gts = new GlobalTripleStore(); try
>>>> (SparqlResult result = gts.executeSparql(queryString)) {
>>>> ResultSet resultSet = (ResultSet) result.getResult(); while
>>>> (resultSet.hasNext()) { QuerySolution sol = resultSet.next();
>>>> int devices = sol.get("count_devices").asLiteral().getInt();
>>>> int observations =sol.get("count_o").asLiteral().getInt();
>>>> statistics.put("devices", resources); statistics.put("o",
>>>> observations); } } catch (SparqlExecutionException e) { // TODO
>>>> Auto-generated catch block e.printStackTrace(); } return
>>>> statistics; } |
>>>
>>>
>
Re: SPARQL with UNION returning TDBTransactionException
Posted by "ajs6f@virginia.edu" <aj...@virginia.edu>.
Try using a service like Github Gist. Is it possible that only one of the legs of the query has results in it? Have you confirmed that _neither_ of the legs executed separately shows the problem?
ajs6f
> On Feb 28, 2017, at 4:51 AM, Andy Seaborne <an...@apache.org> wrote:
>
> What people on the list receive is:
>
> https://lists.apache.org/api/source.lua/8d17e5299cbbe585e7d45ff8ce156021162a9e16fe77818d8f7cff6c@%3Cusers.jena.apache.org%3E
>
> Looks like HTML to text conversion.
>
>> On 27/02/17 23:58, George News wrote:
>> But the funny thing is that in both cases (with and without UNION) the code is the same. I know I close the transaction, but I don’t understand why in one case it works and in the other no.
>
> Probably you close the transaction before the resultset is all consumed.
>
> Some work is done on execSelect so internally, the use of the dataset can finish early.
>
> UNION has two branches calculated separately.
>
> It depends on the real query.
>
> Andy
>
>>
>> I would like to ask another thing: In a @requestscope is the reading transaction automatically close when finished the REST processing or is it mandatory to call dataset.end()?
>>
>> I don't knw why example code is unreadable. I have perfectly seen the code.
>>
>> Thanks a lot
>> Jorge
>>
>> Sent from jlanza_lumia820
>>
>> From: Andy Seaborne
>> Sent: martes, 28 de febrero de 2017 0:12
>> To: users@jena.apache.org
>> Subject: Re: SPARQL with UNION returning TDBTransactionException
>>
>> Unreadable.
>>
>> -------------------------
>>
>> Probably you are passing the result stream out of the transaction.
>>
>> Reading a ResultSet requires reading the dataset and must be inside a
>> transaction when the calls to hasNext/next are happening.
>>
>> Andy
>>
>>> On 27/02/17 18:18, George News wrote:
>>> |public SparqlResult executeSparql(String sparql) throws
>>> SparqlExecutionException { String queryString = sparql; Query query =
>>> QueryFactory.create(queryString); dataset.begin(ReadWrite.READ); try {
>>> QueryExecution qExec = QueryExecutionFactory.create(query, getModel());
>>> // System.out.println(qExec.getQuery().serialize()); //
>>> System.out.println(qExec.getQuery().toString()); SparqlResult result; if
>>> (query.isSelectType()) { result = new SparqlResult(qExec.execSelect(),
>>> qExec); } else if (query.isDescribeType()) { result = new
>>> SparqlResult(qExec.execDescribe(), qExec); } else if (query.isAskType())
>>> { result = new SparqlResult(qExec.execAsk(), qExec); } else if
>>> (query.isConstructType()) { result = new
>>> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
>>> SparqlExecutionException("Unsupported query type: " +
>>> query.getQueryType()); } return result; } finally { dataset.end(); }
>>> private Map<String, Integer> getSummaryStatistics() { String queryString
>>> = "THE_ONE"; Map<String, Integer> statistics = new HashMap<>();
>>> GlobalTripleStore gts = new GlobalTripleStore(); try (SparqlResult
>>> result = gts.executeSparql(queryString)) { ResultSet resultSet =
>>> (ResultSet) result.getResult(); while (resultSet.hasNext()) {
>>> QuerySolution sol = resultSet.next(); int devices =
>>> sol.get("count_devices").asLiteral().getInt(); int observations
>>> =sol.get("count_o").asLiteral().getInt(); statistics.put("devices",
>>> resources); statistics.put("o", observations); } } catch
>>> (SparqlExecutionException e) { // TODO Auto-generated catch block
>>> e.printStackTrace(); } return statistics; } |
>>
>>
Re: SPARQL with UNION returning TDBTransactionException
Posted by "A. Soroka" <aj...@virginia.edu>.
I think the assumption in that example is just that you might not be done with the transaction, but Andy can clarify if needed.
---
A. Soroka
The University of Virginia Library
> On Feb 28, 2017, at 10:42 AM, George News <ge...@gmx.net> wrote:
>
> On 28/02/2017 16:12, A. Soroka wrote:
>> Have you looked at:
>>
>> https://jena.apache.org/documentation/rdfconnection/
>> https://jena.apache.org/documentation/txn/
>
> I didn't know about the new Java 8 interface. Pretty cool ;)
>
> BTW in https://jena.apache.org/documentation/txn/transactions_api.html I
> think there is an error in the second piece of code, isn't it missing a
> dataset.end() to finish the previously open transaction? Or are the read
> transactions automatically closed?
>
>> ---
>> A. Soroka
>> The University of Virginia Library
>>
>>> On Feb 28, 2017, at 10:05 AM, George News <ge...@gmx.net> wrote:
>>>
>>>
>>> In this sense, one option for including in Jena could be to enable the
>>> option to create a QueryExecution with transaction included, in order to
>>> avoid some issues like that.
>>
>>
Re: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
On 28/02/2017 16:12, A. Soroka wrote:
> Have you looked at:
>
> https://jena.apache.org/documentation/rdfconnection/
> https://jena.apache.org/documentation/txn/
I didn't know about the new Java 8 interface. Pretty cool ;)
BTW in https://jena.apache.org/documentation/txn/transactions_api.html I
think there is an error in the second piece of code, isn't it missing a
dataset.end() to finish the previously open transaction? Or are the read
transactions automatically closed?
> ---
> A. Soroka
> The University of Virginia Library
>
>> On Feb 28, 2017, at 10:05 AM, George News <ge...@gmx.net> wrote:
>>
>>
>> In this sense, one option for including in Jena could be to enable the
>> option to create a QueryExecution with transaction included, in order to
>> avoid some issues like that.
>
>
Re: SPARQL with UNION returning TDBTransactionException
Posted by "A. Soroka" <aj...@virginia.edu>.
Have you looked at:
https://jena.apache.org/documentation/rdfconnection/
https://jena.apache.org/documentation/txn/
---
A. Soroka
The University of Virginia Library
> On Feb 28, 2017, at 10:05 AM, George News <ge...@gmx.net> wrote:
>
>
> In this sense, one option for including in Jena could be to enable the
> option to create a QueryExecution with transaction included, in order to
> avoid some issues like that.
Re: SPARQL with UNION returning TDBTransactionException
Posted by Andy Seaborne <an...@apache.org>.
On 28/02/17 17:26, George News wrote:
> On 28/02/2017 17:35, Rob Vesse wrote:
>> What you need to remember is that query execution is streaming lazy
>> evaluation. So each time you call hasNext()/next() the minimum amount
>> of work needed to compute the next answer, If any, is done. When you
>> convert the ResultSet into a list you\u2019re doing all that work up front
>> once. When you iterate over the copied Data it is just a static list
>> of the previously computed results. Iterating over a static list has
>> very little overhead computationally, the downside is that it may
>> have a lot of memory overhead if you have a extremely large results.
>> This is a standard space time trade-off and you have to decide what
>> makes sense in your applications context.
>
> Then between ResultSetFormatter.toList or ResultSetFactory.copyResults
> the different is none, isn't it?
Different return types, both disconnect the results from the dataset.
One creates a List<QuerySolution>, the other returns a new
ResultSetRewindable.
It is better to not pass out the results - instead, pass in some code to
handle the results (e.g. using java8 lambda).
Andy
>
> Sorry for the big thread.
>
> Jorge
>
>> Rob
>>
>> On 28/02/2017 16:19, "George News" <ge...@gmx.net> wrote:
>>
>>
>> On 28/02/2017 16:59, Andy Seaborne wrote:
>>>
>>> [... snip ...]
>>>> In this sense, one option for including in Jena could be to
>>>> enable the option to create a QueryExecution with transaction
>>>> included, in order to avoid some issues like that.
>>>
>>> That's what ResultSetFormatter.toList or
>>> ResultSetFactory.copyResults do.
>>
>> +1 but I don't want to iterate twice over the same list of data.
>> Although at the end I think it would be the easiest way to do it and
>> avoid extra issues ;)
>>
>>
>>> Andy
>>>
>>
>>
>>
>>
>>
>>
Re: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
On 28/02/2017 17:35, Rob Vesse wrote:
> What you need to remember is that query execution is streaming lazy
> evaluation. So each time you call hasNext()/next() the minimum amount
> of work needed to compute the next answer, If any, is done. When you
> convert the ResultSet into a list you\u2019re doing all that work up front
> once. When you iterate over the copied Data it is just a static list
> of the previously computed results. Iterating over a static list has
> very little overhead computationally, the downside is that it may
> have a lot of memory overhead if you have a extremely large results.
> This is a standard space time trade-off and you have to decide what
> makes sense in your applications context.
Then between ResultSetFormatter.toList or ResultSetFactory.copyResults
the different is none, isn't it?
Sorry for the big thread.
Jorge
> Rob
>
> On 28/02/2017 16:19, "George News" <ge...@gmx.net> wrote:
>
>
> On 28/02/2017 16:59, Andy Seaborne wrote:
>>
>> [... snip ...]
>>> In this sense, one option for including in Jena could be to
>>> enable the option to create a QueryExecution with transaction
>>> included, in order to avoid some issues like that.
>>
>> That's what ResultSetFormatter.toList or
>> ResultSetFactory.copyResults do.
>
> +1 but I don't want to iterate twice over the same list of data.
> Although at the end I think it would be the easiest way to do it and
> avoid extra issues ;)
>
>
>> Andy
>>
>
>
>
>
>
>
Re: SPARQL with UNION returning TDBTransactionException
Posted by Rob Vesse <rv...@dotnetrdf.org>.
What you need to remember is that query execution is streaming lazy evaluation. So each time you call hasNext()/next() the minimum amount of work needed to compute the next answer, If any, is done. When you convert the ResultSet into a list you’re doing all that work up front once. When you iterate over the copied Data it is just a static list of the previously computed results. Iterating over a static list has very little overhead computationally, the downside is that it may have a lot of memory overhead if you have a extremely large results. This is a standard space time trade-off and you have to decide what makes sense in your applications context.
Rob
On 28/02/2017 16:19, "George News" <ge...@gmx.net> wrote:
On 28/02/2017 16:59, Andy Seaborne wrote:
>
> [... snip ...]
>> In this sense, one option for including in Jena could be to enable the
>> option to create a QueryExecution with transaction included, in order to
>> avoid some issues like that.
>
> That's what ResultSetFormatter.toList or ResultSetFactory.copyResults do.
+1 but I don't want to iterate twice over the same list of data.
Although at the end I think it would be the easiest way to do it and
avoid extra issues ;)
> Andy
>
Re: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
On 28/02/2017 16:59, Andy Seaborne wrote:
>
> [... snip ...]
>> In this sense, one option for including in Jena could be to enable the
>> option to create a QueryExecution with transaction included, in order to
>> avoid some issues like that.
>
> That's what ResultSetFormatter.toList or ResultSetFactory.copyResults do.
+1 but I don't want to iterate twice over the same list of data.
Although at the end I think it would be the easiest way to do it and
avoid extra issues ;)
> Andy
>
Re: SPARQL with UNION returning TDBTransactionException
Posted by Andy Seaborne <an...@apache.org>.
On 28/02/17 15:05, George News wrote:
>
>
> On 28/02/2017 10:51, Andy Seaborne wrote:
>> What people on the list receive is:
>>
>> https://lists.apache.org/api/source.lua/8d17e5299cbbe585e7d45ff8ce156021162a9e16fe77818d8f7cff6c@%3Cusers.jena.apache.org%3E
>>
>
> Ok. So the list is text based ;) Fine for next time.
>>
>> Looks like HTML to text conversion.
>>
>> On 27/02/17 23:58, George News wrote:
>>> But the funny thing is that in both cases (with and without UNION)
>>> the code is the same. I know I close the transaction, but I don\u2019t
>>> understand why in one case it works and in the other no.
>>
>> Probably you close the transaction before the resultset is all
>> consumed.
>>
>> Some work is done on execSelect so internally, the use of the
>> dataset can finish early.
>>
>> UNION has two branches calculated separately.
>
> I was supposing that. At the end I have included the dataset in my own
> ResultSetClosable class, so this way I can call dataset.end() on
> ResultSet close. It seems that it works this way, it is not the more
> elegant one, but it works.
>
> In this sense, one option for including in Jena could be to enable the
> option to create a QueryExecution with transaction included, in order to
> avoid some issues like that.
That's what ResultSetFormatter.toList or ResultSetFactory.copyResults do.
Andy
>
>> It depends on the real query.
>>
>> Andy
>>
>>>
>>> I would like to ask another thing: In a @requestscope is the
>>> reading transaction automatically close when finished the REST
>>> processing or is it mandatory to call dataset.end()?
>>>
>>> I don't knw why example code is unreadable. I have perfectly seen
>>> the code.
>>>
>>> Thanks a lot Jorge
>>>
>>> Sent from jlanza_lumia820
>>>
>>> From: Andy Seaborne Sent: martes, 28 de febrero de 2017 0:12 To:
>>> users@jena.apache.org Subject: Re: SPARQL with UNION returning
>>> TDBTransactionException
>>>
>>> Unreadable.
>>>
>>> -------------------------
>>>
>>> Probably you are passing the result stream out of the transaction.
>>>
>>> Reading a ResultSet requires reading the dataset and must be inside
>>> a transaction when the calls to hasNext/next are happening.
>>>
>>> Andy
>>>
>>> On 27/02/17 18:18, George News wrote:
>>>> |public SparqlResult executeSparql(String sparql) throws
>>>> SparqlExecutionException { String queryString = sparql; Query
>>>> query = QueryFactory.create(queryString);
>>>> dataset.begin(ReadWrite.READ); try { QueryExecution qExec =
>>>> QueryExecutionFactory.create(query, getModel()); //
>>>> System.out.println(qExec.getQuery().serialize()); //
>>>> System.out.println(qExec.getQuery().toString()); SparqlResult
>>>> result; if (query.isSelectType()) { result = new
>>>> SparqlResult(qExec.execSelect(), qExec); } else if
>>>> (query.isDescribeType()) { result = new
>>>> SparqlResult(qExec.execDescribe(), qExec); } else if
>>>> (query.isAskType()) { result = new SparqlResult(qExec.execAsk(),
>>>> qExec); } else if (query.isConstructType()) { result = new
>>>> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
>>>> SparqlExecutionException("Unsupported query type: " +
>>>> query.getQueryType()); } return result; } finally {
>>>> dataset.end(); } private Map<String, Integer>
>>>> getSummaryStatistics() { String queryString = "THE_ONE";
>>>> Map<String, Integer> statistics = new HashMap<>();
>>>> GlobalTripleStore gts = new GlobalTripleStore(); try
>>>> (SparqlResult result = gts.executeSparql(queryString)) {
>>>> ResultSet resultSet = (ResultSet) result.getResult(); while
>>>> (resultSet.hasNext()) { QuerySolution sol = resultSet.next(); int
>>>> devices = sol.get("count_devices").asLiteral().getInt(); int
>>>> observations =sol.get("count_o").asLiteral().getInt();
>>>> statistics.put("devices", resources); statistics.put("o",
>>>> observations); } } catch (SparqlExecutionException e) { // TODO
>>>> Auto-generated catch block e.printStackTrace(); } return
>>>> statistics; } |
>>>
>>>
>>
Re: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
On 28/02/2017 10:51, Andy Seaborne wrote:
> What people on the list receive is:
>
> https://lists.apache.org/api/source.lua/8d17e5299cbbe585e7d45ff8ce156021162a9e16fe77818d8f7cff6c@%3Cusers.jena.apache.org%3E
>
Ok. So the list is text based ;) Fine for next time.
>
> Looks like HTML to text conversion.
>
> On 27/02/17 23:58, George News wrote:
>> But the funny thing is that in both cases (with and without UNION)
>> the code is the same. I know I close the transaction, but I don\u2019t
>> understand why in one case it works and in the other no.
>
> Probably you close the transaction before the resultset is all
> consumed.
>
> Some work is done on execSelect so internally, the use of the
> dataset can finish early.
>
> UNION has two branches calculated separately.
I was supposing that. At the end I have included the dataset in my own
ResultSetClosable class, so this way I can call dataset.end() on
ResultSet close. It seems that it works this way, it is not the more
elegant one, but it works.
In this sense, one option for including in Jena could be to enable the
option to create a QueryExecution with transaction included, in order to
avoid some issues like that.
> It depends on the real query.
>
> Andy
>
>>
>> I would like to ask another thing: In a @requestscope is the
>> reading transaction automatically close when finished the REST
>> processing or is it mandatory to call dataset.end()?
>>
>> I don't knw why example code is unreadable. I have perfectly seen
>> the code.
>>
>> Thanks a lot Jorge
>>
>> Sent from jlanza_lumia820
>>
>> From: Andy Seaborne Sent: martes, 28 de febrero de 2017 0:12 To:
>> users@jena.apache.org Subject: Re: SPARQL with UNION returning
>> TDBTransactionException
>>
>> Unreadable.
>>
>> -------------------------
>>
>> Probably you are passing the result stream out of the transaction.
>>
>> Reading a ResultSet requires reading the dataset and must be inside
>> a transaction when the calls to hasNext/next are happening.
>>
>> Andy
>>
>> On 27/02/17 18:18, George News wrote:
>>> |public SparqlResult executeSparql(String sparql) throws
>>> SparqlExecutionException { String queryString = sparql; Query
>>> query = QueryFactory.create(queryString);
>>> dataset.begin(ReadWrite.READ); try { QueryExecution qExec =
>>> QueryExecutionFactory.create(query, getModel()); //
>>> System.out.println(qExec.getQuery().serialize()); //
>>> System.out.println(qExec.getQuery().toString()); SparqlResult
>>> result; if (query.isSelectType()) { result = new
>>> SparqlResult(qExec.execSelect(), qExec); } else if
>>> (query.isDescribeType()) { result = new
>>> SparqlResult(qExec.execDescribe(), qExec); } else if
>>> (query.isAskType()) { result = new SparqlResult(qExec.execAsk(),
>>> qExec); } else if (query.isConstructType()) { result = new
>>> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
>>> SparqlExecutionException("Unsupported query type: " +
>>> query.getQueryType()); } return result; } finally {
>>> dataset.end(); } private Map<String, Integer>
>>> getSummaryStatistics() { String queryString = "THE_ONE";
>>> Map<String, Integer> statistics = new HashMap<>();
>>> GlobalTripleStore gts = new GlobalTripleStore(); try
>>> (SparqlResult result = gts.executeSparql(queryString)) {
>>> ResultSet resultSet = (ResultSet) result.getResult(); while
>>> (resultSet.hasNext()) { QuerySolution sol = resultSet.next(); int
>>> devices = sol.get("count_devices").asLiteral().getInt(); int
>>> observations =sol.get("count_o").asLiteral().getInt();
>>> statistics.put("devices", resources); statistics.put("o",
>>> observations); } } catch (SparqlExecutionException e) { // TODO
>>> Auto-generated catch block e.printStackTrace(); } return
>>> statistics; } |
>>
>>
>
Re: SPARQL with UNION returning TDBTransactionException
Posted by Andy Seaborne <an...@apache.org>.
What people on the list receive is:
https://lists.apache.org/api/source.lua/8d17e5299cbbe585e7d45ff8ce156021162a9e16fe77818d8f7cff6c@%3Cusers.jena.apache.org%3E
Looks like HTML to text conversion.
On 27/02/17 23:58, George News wrote:
> But the funny thing is that in both cases (with and without UNION) the code is the same. I know I close the transaction, but I don\u2019t understand why in one case it works and in the other no.
Probably you close the transaction before the resultset is all consumed.
Some work is done on execSelect so internally, the use of the dataset
can finish early.
UNION has two branches calculated separately.
It depends on the real query.
Andy
>
> I would like to ask another thing: In a @requestscope is the reading transaction automatically close when finished the REST processing or is it mandatory to call dataset.end()?
>
> I don't knw why example code is unreadable. I have perfectly seen the code.
>
> Thanks a lot
> Jorge
>
> Sent from jlanza_lumia820
>
> From: Andy Seaborne
> Sent: martes, 28 de febrero de 2017 0:12
> To: users@jena.apache.org
> Subject: Re: SPARQL with UNION returning TDBTransactionException
>
> Unreadable.
>
> -------------------------
>
> Probably you are passing the result stream out of the transaction.
>
> Reading a ResultSet requires reading the dataset and must be inside a
> transaction when the calls to hasNext/next are happening.
>
> Andy
>
> On 27/02/17 18:18, George News wrote:
>> |public SparqlResult executeSparql(String sparql) throws
>> SparqlExecutionException { String queryString = sparql; Query query =
>> QueryFactory.create(queryString); dataset.begin(ReadWrite.READ); try {
>> QueryExecution qExec = QueryExecutionFactory.create(query, getModel());
>> // System.out.println(qExec.getQuery().serialize()); //
>> System.out.println(qExec.getQuery().toString()); SparqlResult result; if
>> (query.isSelectType()) { result = new SparqlResult(qExec.execSelect(),
>> qExec); } else if (query.isDescribeType()) { result = new
>> SparqlResult(qExec.execDescribe(), qExec); } else if (query.isAskType())
>> { result = new SparqlResult(qExec.execAsk(), qExec); } else if
>> (query.isConstructType()) { result = new
>> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
>> SparqlExecutionException("Unsupported query type: " +
>> query.getQueryType()); } return result; } finally { dataset.end(); }
>> private Map<String, Integer> getSummaryStatistics() { String queryString
>> = "THE_ONE"; Map<String, Integer> statistics = new HashMap<>();
>> GlobalTripleStore gts = new GlobalTripleStore(); try (SparqlResult
>> result = gts.executeSparql(queryString)) { ResultSet resultSet =
>> (ResultSet) result.getResult(); while (resultSet.hasNext()) {
>> QuerySolution sol = resultSet.next(); int devices =
>> sol.get("count_devices").asLiteral().getInt(); int observations
>> =sol.get("count_o").asLiteral().getInt(); statistics.put("devices",
>> resources); statistics.put("o", observations); } } catch
>> (SparqlExecutionException e) { // TODO Auto-generated catch block
>> e.printStackTrace(); } return statistics; } |
>
>
RE: SPARQL with UNION returning TDBTransactionException
Posted by George News <ge...@gmx.net>.
But the funny thing is that in both cases (with and without UNION) the code is the same. I know I close the transaction, but I don’t understand why in one case it works and in the other no.
I would like to ask another thing: In a @requestscope is the reading transaction automatically close when finished the REST processing or is it mandatory to call dataset.end()?
I don't knw why example code is unreadable. I have perfectly seen the code.
Thanks a lot
Jorge
Sent from jlanza_lumia820
From: Andy Seaborne
Sent: martes, 28 de febrero de 2017 0:12
To: users@jena.apache.org
Subject: Re: SPARQL with UNION returning TDBTransactionException
Unreadable.
-------------------------
Probably you are passing the result stream out of the transaction.
Reading a ResultSet requires reading the dataset and must be inside a
transaction when the calls to hasNext/next are happening.
Andy
On 27/02/17 18:18, George News wrote:
> |public SparqlResult executeSparql(String sparql) throws
> SparqlExecutionException { String queryString = sparql; Query query =
> QueryFactory.create(queryString); dataset.begin(ReadWrite.READ); try {
> QueryExecution qExec = QueryExecutionFactory.create(query, getModel());
> // System.out.println(qExec.getQuery().serialize()); //
> System.out.println(qExec.getQuery().toString()); SparqlResult result; if
> (query.isSelectType()) { result = new SparqlResult(qExec.execSelect(),
> qExec); } else if (query.isDescribeType()) { result = new
> SparqlResult(qExec.execDescribe(), qExec); } else if (query.isAskType())
> { result = new SparqlResult(qExec.execAsk(), qExec); } else if
> (query.isConstructType()) { result = new
> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
> SparqlExecutionException("Unsupported query type: " +
> query.getQueryType()); } return result; } finally { dataset.end(); }
> private Map<String, Integer> getSummaryStatistics() { String queryString
> = "THE_ONE"; Map<String, Integer> statistics = new HashMap<>();
> GlobalTripleStore gts = new GlobalTripleStore(); try (SparqlResult
> result = gts.executeSparql(queryString)) { ResultSet resultSet =
> (ResultSet) result.getResult(); while (resultSet.hasNext()) {
> QuerySolution sol = resultSet.next(); int devices =
> sol.get("count_devices").asLiteral().getInt(); int observations
> =sol.get("count_o").asLiteral().getInt(); statistics.put("devices",
> resources); statistics.put("o", observations); } } catch
> (SparqlExecutionException e) { // TODO Auto-generated catch block
> e.printStackTrace(); } return statistics; } |
Re: SPARQL with UNION returning TDBTransactionException
Posted by Andy Seaborne <an...@apache.org>.
Unreadable.
-------------------------
Probably you are passing the result stream out of the transaction.
Reading a ResultSet requires reading the dataset and must be inside a
transaction when the calls to hasNext/next are happening.
Andy
On 27/02/17 18:18, George News wrote:
> |public SparqlResult executeSparql(String sparql) throws
> SparqlExecutionException { String queryString = sparql; Query query =
> QueryFactory.create(queryString); dataset.begin(ReadWrite.READ); try {
> QueryExecution qExec = QueryExecutionFactory.create(query, getModel());
> // System.out.println(qExec.getQuery().serialize()); //
> System.out.println(qExec.getQuery().toString()); SparqlResult result; if
> (query.isSelectType()) { result = new SparqlResult(qExec.execSelect(),
> qExec); } else if (query.isDescribeType()) { result = new
> SparqlResult(qExec.execDescribe(), qExec); } else if (query.isAskType())
> { result = new SparqlResult(qExec.execAsk(), qExec); } else if
> (query.isConstructType()) { result = new
> SparqlResult(qExec.execConstruct(), qExec); } else { throw new
> SparqlExecutionException("Unsupported query type: " +
> query.getQueryType()); } return result; } finally { dataset.end(); }
> private Map<String, Integer> getSummaryStatistics() { String queryString
> = "THE_ONE"; Map<String, Integer> statistics = new HashMap<>();
> GlobalTripleStore gts = new GlobalTripleStore(); try (SparqlResult
> result = gts.executeSparql(queryString)) { ResultSet resultSet =
> (ResultSet) result.getResult(); while (resultSet.hasNext()) {
> QuerySolution sol = resultSet.next(); int devices =
> sol.get("count_devices").asLiteral().getInt(); int observations
> =sol.get("count_o").asLiteral().getInt(); statistics.put("devices",
> resources); statistics.put("o", observations); } } catch
> (SparqlExecutionException e) { // TODO Auto-generated catch block
> e.printStackTrace(); } return statistics; } |