Dear all,

I am sorry for my incompetence but I have a problem with indexing labels using 
Apache Jena. I have already checked several posts about this topic but can’t 
find my error. Is there anyone who could help me please?

My text-config.ttl file looks like this:
> @prefix :        <http://localhost/jena_example/#> .
> @prefix rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
> @prefix rdfs:    <http://www.w3.org/2000/01/rdf-schema#> .
> @prefix tdb:     <http://jena.hpl.hp.com/2008/tdb#> .
> @prefix ja:      <http://jena.hpl.hp.com/2005/11/Assembler#> .
> @prefix text:    <http://jena.apache.org/text#> .
> 
> # TDB
> [] ja:loadClass "org.apache.jena.tdb.TDB" .
> tdb:DatasetTDB  rdfs:subClassOf  ja:RDFDataset .
> tdb:GraphTDB    rdfs:subClassOf  ja:Model .
> 
> # Text
> [] ja:loadClass "org.apache.jena.query.text.TextQuery" .
> text:TextDataset      rdfs:subClassOf   ja:RDFDataset .
> text:TextIndexLucene  rdfs:subClassOf   text:TextIndex .
> 
> ## ---------------------------------------------------------------
> ## This URI must be fixed - it's used to assemble the text dataset.
> 
> :text_dataset rdf:type     text:TextDataset ;
>     text:dataset   <#dataset> ;
>     text:index     <#indexLucene> ;
>     .
> 
> <#dataset> rdf:type      tdb:DatasetTDB ;
>     tdb:location "storage" ;
>     ## In the example, this would hide the real default graph.
>     # tdb:unionDefaultGraph true ;
>     .
> 
> <#indexLucene> a text:TextIndexLucene ;
>     #text:directory <file:Lucene> ;
>     text:directory <file:storage> ;
>     text:entityMap <#entMap> ;
>     .
> 
> <#entMap> a text:EntityMap ;
>     text:entityField      "uri" ;
>     text:defaultField     "text" ; ## Must be defined in the text:maps
>     text:map (
>          # rdfs:label            
>          [ text:field "text" ; text:predicate rdfs:label ]
>          ) .

I have a dataset file from dbpedia with some labels that I load and index with 
these commands:
> java -cp fuseki-server.jar tdb.tdbloader --tdb=config.ttl 
> infobox_property_definitions_en.ttl 
> java -cp fuseki-server.jar jena.textindexer --desc=config.ttl 

To test for the indexed labels I tried the following query:
> PREFIX text: <http://jena.apache.org/text#>
> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
> SELECT * 
> { ?s text:query (rdfs:label "Stage") ;
>     rdfs:label ?label
> }
> LIMIT 10

With this command:
> java -cp fuseki-server.jar tdb.tdbquery --time --tdb=config.ttl 
> --query=query.txt

However, I just get the following results:
> WARN  Failed to find the text index : tried context and as a text-enabled 
> dataset
> WARN  No text index - no text search performed
> ----------------------------------------------------------
> | s                                      | label         |
> ==========================================================
> | <http://dbpedia.org/property/colwidth> | "colwidth"@en |
> | <http://dbpedia.org/property/voy>      | "voy"@en      |
> | <http://dbpedia.org/property/n>        | "n"@en        |
> | <http://dbpedia.org/property/v>        | "v"@en        |
> | <http://dbpedia.org/property/b>        | "b"@en        |
> | <http://dbpedia.org/property/s>        | "s"@en        |
> | <http://dbpedia.org/property/d>        | "d"@en        |
> | <http://dbpedia.org/property/name>     | "Name"@en     |
> | <http://dbpedia.org/property/alt>      | "Alt"@en      |
> | <http://dbpedia.org/property/caption>  | "Caption"@en  |
> ----------------------------------------------------------
> Time: 0,065 sec

Obviously, these are not the desired results and the script has a problem 
finding the text index. Just for clarification: I have decided to use a TDB 
backed solution because my aim is to reproduce some dbpedia data locally but 
without in-memory load. Actually, my intention is not to use the Fuseki Server 
but it seems that it is the only solution to use text indexing.

Thank you very much for your help.

Best regards
Philipp

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