On 23/09/16 09:35, Mikael Pesonen wrote:
Hi,
I have another query that is behaving illogically to me. I am searching
for terms in SKOS vocabulary and also need to retrieve topmost level
concept for each search result.
This query returns entire skos:broader hierarchy for search results and
works in a second (marked related lines with bold)
SELECT ?graph ?concept
(group_concat(DISTINCT
concat(?prefLabelm,"@",lang(?prefLabelm));separator="NEWLINE") AS
?prefLabelms)
(group_concat(DISTINCT
concat(?prefLabel,"@",lang(?prefLabel));separator="NEWLINE") AS
?prefLabels)
(group_concat(DISTINCT
concat(?altLabelm,"@",lang(?altLabelm));separator="NEWLINE") AS
?altLabelms)
(group_concat(DISTINCT
concat(?altLabel,"@",lang(?altLabel));separator="NEWLINE") AS ?altLabels)
(group_concat(DISTINCT
concat(?def1,"@",lang(?def1));separator="NEWLINENEWLINE") AS ?defs1)
(group_concat(DISTINCT
concat(?def2,"@",lang(?def2));separator="NEWLINENEWLINE") AS ?defs2)
*(group_concat(DISTINCT
concat(?topConceptLabel,"@",lang(?topConceptLabel));separator="/") AS
?topConceptLabels)*
WHERE
{
GRAPH ?graph { ?graph dcterms:subject "MEDICAL" }
GRAPH ?graph
{
{
SELECT DISTINCT ?concept ?prefLabelm ?altLabelm WHERE
{
{?concept skos:prefLabel ?prefLabelm FILTER (
(lang(?prefLabelm) = "fi" || lang(?prefLabelm) = "la-FI") &&
REGEX(?prefLabelm, "culo", "i"))}
UNION
{?concept skos:altLabel ?altLabelm FILTER (
(lang(?altLabelm) = "fi" || lang(?altLabelm) = "la-FI") &&
REGEX(?altLabelm, "culo", "i"))}
}
limit 200
}
?concept skos:prefLabel ?prefLabel .
OPTIONAL { ?concept skos:altLabel ?altLabel }
OPTIONAL { ?concept skos:definition ?def1 . OPTIONAL {?def1
rdf:value ?def2 } }
*OPTIONAL { ?concept skos:broader* ?topConcept . ?topConcept
skos:prefLabel ?topConceptLabel FILTER ( lang(?topConceptLabel) = "fi") }*
}
}
GROUP BY ?graph ?concept
But this is what I tried first to get only the one topmost broader for
each, but it takes 17 seconds to run:
SELECT ?graph ?concept *?topConceptLabel*
(group_concat(DISTINCT
concat(?prefLabelm,"@",lang(?prefLabelm));separator="NEWLINE") AS
?prefLabelms)
(group_concat(DISTINCT
concat(?prefLabel,"@",lang(?prefLabel));separator="NEWLINE") AS
?prefLabels)
(group_concat(DISTINCT
concat(?altLabelm,"@",lang(?altLabelm));separator="NEWLINE") AS
?altLabelms)
(group_concat(DISTINCT
concat(?altLabel,"@",lang(?altLabel));separator="NEWLINE") AS ?altLabels)
(group_concat(DISTINCT
concat(?def1,"@",lang(?def1));separator="NEWLINENEWLINE") AS ?defs1)
(group_concat(DISTINCT
concat(?def2,"@",lang(?def2));separator="NEWLINENEWLINE") AS ?defs2)
WHERE
{
GRAPH ?graph { ?graph dcterms:subject "MEDICAL" }
GRAPH ?graph
{
{
SELECT DISTINCT ?concept ?prefLabelm ?altLabelm WHERE
{
{?concept skos:prefLabel ?prefLabelm FILTER (
(lang(?prefLabelm) = "fi" || lang(?prefLabelm) = "la-FI") &&
REGEX(?prefLabelm, "culo", "i"))}
UNION
{?concept skos:altLabel ?altLabelm FILTER (
(lang(?altLabelm) = "fi" || lang(?altLabelm) = "la-FI") &&
REGEX(?altLabelm, "culo", "i"))}
}
limit 200
}
?concept skos:prefLabel ?prefLabel .
OPTIONAL { ?concept skos:altLabel ?altLabel }
OPTIONAL { ?concept skos:definition ?def1 . OPTIONAL {?def1
rdf:value ?def2 } }
*OPTIONAL { ?topConcept skos:topConceptOf ?graph . ?concept
skos:broader* ?topConcept . ?topConcept skos:prefLabel ?topConceptLabel
FILTER ( lang(?topConceptLabel) = "fi") }*
You can format queries with qparse or use sparql.org.
First:
GRAPH ?graph
{
...
OPTIONAL
{ ?concept (skos:broader)* ?topConcept .
?topConcept skos:prefLabel ?topConceptLabel
FILTER ( lang(?topConceptLabel) = "fi" )
}
Second:
GRAPH ?graph
{
...
OPTIONAL
{ ?topConcept skos:topConceptOf ?graph .
?concept (skos:broader)* ?topConcept .
?topConcept skos:prefLabel ?topConceptLabel
FILTER ( lang(?topConceptLabel) = "fi" )
}
so the 2nd query does an extra
"?topConcept skos:topConceptOf ?graph ."
before the path.
Try putting it after.
Also,use a version with the path performance fix.
Because you have a group and DISTINCT, this may be several matches but
this is hidden.
Also, GRAPH ?graph { ... OPTIONAL { use of ?graph .... } ... }
means that the engine may have to separate those two uses of ?graph at
the point the BGP executes and sort it out later. The earlier
GRAPH ?graph { ?graph dcterms:subject "MEDICAL" }
may not have so much effect limiting the execution search.
Andy
}
}
GROUP BY ?graph ?concept *?topConceptLabel*
The speed issue seems totally illogical to me but there must be a
correct way to perform the latter query then?
Br,
Mikael
