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https://issues.apache.org/jira/browse/JENA-2228?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17466540#comment-17466540
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Andy Seaborne commented on JENA-2228:
-------------------------------------
If it is for SPARQL execution, and to catch triple patterns that become
concrete during Basic Graph Pattern execution, then the bloom filter should be
NodeIds, not Nodes because basic graph pattern matching is done with NodeIds,
and that's what is in the B+Tree indexes. Bound variables that are not used in
another part of the execution do not get covered back to Nodes.
If it is a different access path, for example graph.contains with concrete
argument(s), then a bloom filter of nodes makes some sense. To calculate it
will need either reading the B+Tree (in NodeIds), converting to Nodes, which is
what NodeTupleTable will do for you.
> Does Fuseki2 use TDB indexes or indexes for in-memory store?
> ------------------------------------------------------------
>
> Key: JENA-2228
> URL: https://issues.apache.org/jira/browse/JENA-2228
> Project: Apache Jena
> Issue Type: Question
> Components: Fuseki, TDB
> Affects Versions: Jena 3.17.0
> Environment: I am running the jena-fuseki-server-3.17.0.jar file from
> jena-fuseki2/jena-fuseki-server/target/ as follows
> {code:java}
> java -Xmx500g -jar fuseki-jenaclone.jar --tdb2 --loc=db/jena
> --timeout=1000000 /jena &{code}
> Reporter: Martin Pekár
> Priority: Major
>
> Based on logging messages inserted into various places in the indexes in the
> TDB module (NodeTupleTableConcrete, TupleIndexBase, NodeTableNative,
> BPlusTree), I can see that the B+ tree is only used once per query. I have
> inserted logging messages for every finding method to see which classes are
> used when querying. I would expect to the the B+ tree be used several times
> per query.
>
> I use the error logging level, and I inserted logging in the class
> constructors to make sure logging worked. I see construction of all the index
> classes.
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