SPARQL - CONSTRUCT 查询性能问题

Question

i've to query a set of statements before i create a new version of an object with the same identifier. With the result i analyse the changes and reuse referenced objects, if the haven't changed. But the following query is aweful and very slow. if there are ~ 1000 object versions, it runs about 120 seconds. and i've to import lot more !

Is there a way to query the statements in a more performant way? I know the "OPTIONAL" is bad, but the properties can be empty.

Thanks

PREFIX schema: <https://schema.org/>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX as: <https://www.w3.org/ns/activitystreams#>

CONSTRUCT {
    ?publication rdf:type ?type ;
        schema:about ?about ;
        schema:about ?about;
        schema:name ?name ;
        as:name ?asname ;
        as:published ?published ;
        as:attributedTo ?attributedTo ;
        schema:creativeWorkStatus ?creativeWorkStatus ;
        schema:dateCreated ?dateCreated ;
        schema:dateModified ?dateModified ;
        schema:description ?description ;
        schema:identifier ?identifier ;
        schema:keywords ?keywords ;
        schema:license ?license ;
        schema:version ?version .
        ?about rdf:type ?aboutType ;
        schema:name ?aboutName ;
        schema:contactPoint ?aboutContactPoint ;
        schema:location ?aboutLocation .
    ?aboutContactPoint rdf:type ?contactPointType ;
        schema:email ?contactPointEmail ;
        schema:name ?contactPointName ;
        schema:telephone?contactPointTelephone .
    ?aboutLocation rdf:type ?locationType ;
        schema:latitude ?locationLatitude ;
      schema:longitude ?locationLongitude ;
      schema:address ?locationAddress .
    # Adress
    ?locationAddress rdf:type ?addressType ;
        schema:addressCountry ?addressCountry ;
        schema:addressLocality ?addressLocality ;
        schema:streetAddress ?addressStreetAddress ;
        schema:postalCode ?addressPostalCode .
}
FROM <http://localhost:8081/camel/fef6dc4b-e1e9-46f5-a34e-8ab5c1600ec4>
WHERE {
    ?publication rdf:type schema:CreativeWork ;
    rdf:type ?type ;
    schema:identifier "6472c8bbf6504b56b473a1e6a10fcc8d".
    OPTIONAL {?publication schema:name ?name . }
    OPTIONAL {?publication as:name ?asname . }
    OPTIONAL {?publication as:published ?published . }
    OPTIONAL {?publication as:attributedTo ?attributedTo . }
    OPTIONAL {?publication schema:creativeWorkStatus ?creativeWorkStatus . }
    OPTIONAL {?publication schema:dateCreated ?dateCreated . }
    OPTIONAL {?publication schema:dateModified ?dateModified . }
    OPTIONAL {?publication schema:description ?description . }
    OPTIONAL {?publication schema:identifier ?identifier . }
    OPTIONAL {?publication schema:keywords ?keywords . }
    OPTIONAL {?publication schema:license ?license . }
    OPTIONAL {?publication schema:version ?version . }
    OPTIONAL {?publication schema:about ?about . }
    # Organization
    OPTIONAL {?publication schema:about/rdf:type ?aboutType . }
    OPTIONAL {?publication schema:about/schema:name ?aboutName . }
    OPTIONAL {?publication schema:about/schema:contactPoint ?aboutContactPoint . }
    OPTIONAL {?publication schema:about/schema:location ?aboutLocation . }
    # ContactPoint
    OPTIONAL {?publication schema:about/schema:contactPoint/rdf:type ?contactPointType . }
    OPTIONAL {?publication schema:about/schema:contactPoint/schema:email ?contactPointEmail . }
    OPTIONAL {?publication schema:about/schema:contactPoint/schema:name ?contactPointName . }
    OPTIONAL {?publication schema:about/schema:contactPoint/schema:telephone?contactPointTelephone . }
    # Place
    OPTIONAL {?publication schema:about/schema:location/rdf:type ?locationType . }
    OPTIONAL {?publication schema:about/schema:location/schema:latitude ?locationLatitude . }
    OPTIONAL {?publication schema:about/schema:location/schema:longitude ?locationLongitude . }
    OPTIONAL {?publication schema:about/schema:location/schema:address ?locationAddress . }
    # Adress
    OPTIONAL {?publication schema:about/schema:location/schema:address/rdf:type ?addressType . }
    OPTIONAL {?publication schema:about/schema:location/schema:address/schema:addressLocality ?addressLocality . }
    OPTIONAL {?publication schema:about/schema:location/schema:address/schema:streetAddress ?addressStreetAddress . }
    OPTIONAL {?publication schema:about/schema:location/schema:address/schema:postalCode ?addressPostalCode . }
    OPTIONAL {?publication schema:about/schema:location/schema:address/schema:addressCountry ?addressCountry . }
}

Answer 1

Use VALUES to avoid OPTIONAL.

    VALUES ?p {
        schema:name
        as:name
        as:published 
        as:attributedTo
        schema:creativeWorkStatus
        schema:dateCreated
        schema:dateModified
        schema:description
        schema:identifier
        schema:keywords
        schema:license
        schema:version
        schema:about
      }
      ?publication ?p ?o .