Search code examples
sparqltriplestoretriples

SPARQL query for some kind of START WITH and CONNECT BY (Oracle)

I'm busy with a proof of concept working with a triple store. I have the following structure:

enter image description here

There are 2 relation types defined (triples). Top-down relation where the child is part of ("isPartOf" its parent and left-right where there are childs that CAN (optional) be replaced ("replaces") by another version of the child.

Also every child have a "isValidStart" triple with a date as object. This means that this child is valid since that date. The last child in a horizontal childgroup can have a relation "isInvalidEnd" that means that after this date this group is invalid.

What I want to do is to build a SPARQL query where I can get the childs of a parent on a specific date. Is that possible with SPARQL and how can I do that?

I know that there is in Oracle any kind of START WITH / CONNECT BY function that do some kind of this stuff...but how do I this in SPARQL world.

Thanks

</metadata/puid/test2> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test1" .
</metadata/puid/test2> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test3> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test2" .
</metadata/puid/test3> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test4> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test3" .
</metadata/puid/test4> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test5> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test4" .
</metadata/puid/test5> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test6> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test4" .
</metadata/puid/test6> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test7> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test4" .
</metadata/puid/test7> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test8> <http://purl.org/dc/terms/replaces> "/metadata/puid/test7" .
</metadata/puid/test8> <http://purl.org/dc/terms/isValidStart> "2015-07-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test9> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test5" .
</metadata/puid/test9> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test10> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test5" .
</metadata/puid/test10> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test11> <http://purl.org/dc/terms/isPartOf> "/metadata/puid/test5" .
</metadata/puid/test11> <http://purl.org/dc/terms/isValidStart> "2015-04-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test12> <http://purl.org/dc/terms/replaces> "/metadata/puid/test9" .
</metadata/puid/test12> <http://purl.org/dc/terms/isValidStart> "2015-07-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test13> <http://purl.org/dc/terms/replaces> "/metadata/puid/test10" .
</metadata/puid/test13> <http://purl.org/dc/terms/isValidStart> "2015-05-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test14> <http://purl.org/dc/terms/replaces> "/metadata/puid/test13" .
</metadata/puid/test14> <http://purl.org/dc/terms/isValidStart> "2015-08-01"^^<http://www.w3.org/2001/XMLSchema#date> .
</metadata/puid/test14> <http://purl.org/dc/terms/isValidEnd> "2015-12-01"^^<http://www.w3.org/2001/XMLSchema#date> .

// disclaimer: I'm new in SPARQL world

Solution

  • I worked on a solution and I found a working solution. I put this method in a function that I can use to find the valid childs below that item (parent). I get a complete tree, with only valid items, when calling this function recursively.

    PREFIX : <http://purl.org/dc/terms/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>

SELECT  ?child ?startDate ?endDate
WHERE
{ 
    # get the valid start values 
    ?child  :isValidStart  ?startDate


    BIND(iri("'||$parent||'") as ?parent) 
    FILTER EXISTS{ {?child :isPartOf ?parent }
                  UNION { 
                    ?child (:replaces)+ ?prevVersion .
                    ?prevVersion :isPartOf ?parent
                   } 
                 }
    # and there was no other valid replacing child
    FILTER NOT EXISTS { ?replacer  :replaces  ?child ;
                                   :isValidStart ?startDateReplacer
                        FILTER (?startDateReplacer <= "'||$selectionDate||'"^^xsd:date)
                      } 

    # where the start was before/at the given date
    FILTER(?startDate <= "'||$selectionDate||'"^^xsd:date)

    OPTIONAL { ?child :isValidEnd ?endDate }

    # and not end date is before/at selection date        
    FILTER NOT EXISTS { FILTER (?endDate <= "'||$selectionDate||'"^^xsd:date) }        
 }