I want the number of distinct occurrences of ?s1 as the object of dbpedia:supports, where ?s1 has the keywords 'batman' as the value of one or more of its properties. Am I correct that both of the following queries express these semantics:
There are 9000 records that use ?s1 as dbpedia:supports: SPARQL Facets (see the “supports” item under the Used As column
When these records are the subject, the number is 34: SPARQL Facets
If they are different, I would be grateful to know how they differ. I notice that the triple ?s1o ?s1ip ?s1 was added to the first query, but doesn’t filter the URI value of ?s1ip to dbpedia:supports.
(Note, both of the above SPARQL queries were generated by FCT service, just proxy the traffic on the Facets links above if you wish to inspect).
Likewise, when I filter the class, I expect to see 34 Work (the count next to Records and the count next to Works should match), but there are instead 171 Works. Same pattern of missing filter on the subject in the SPARQL query.
The Virtuoso Universal Server -Enterprise Edition- BYOL AMI-8-2-0-ami appears to be affected by this issue, i.e., the FCT results are not filtered, and the filter clause appears to be left out of query, and is prepended to the XML document returned in the FCT response. E.g.
HTTP/1.1 200 OK
Server: nginx/1.14.0 (Ubuntu)
Date: Wed, 27 Feb 2019 14:58:15 GMT
Content-Type: text/xml; charset=UTF-8
Connection: close
X-Powered-By: Express
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept
accept-ranges: bytes
Content-Length: 8067
filter (?s1 = <http://xmlns.com/foaf/0.1/Person>) .<fct:facets xmlns:fct="http://openlinksw.com/services/facets/1.0/">
<fct:sparql> select ?s1 as ?c1 count (*) as ?c2 where { select distinct ?s1 {?s1 a <http://www.w3.org/2002/07/owl#Class> . } } group by ?s1 order by desc 2 limit 30 offset 0 </fct:sparql>
<fct:time>42</fct:time>
<fct:complete>yes</fct:complete>
<fct:timeout>15520</fct:timeout>
<fct:db-activity> 2.771K rnd 10.37K seq 1.74K same seg 120 same pg 0 same par 0 disk 0 spec disk 0B / 0 messages 0 fork</fct:db-activity>
<fct:result type="list-count">
<fct:row>
Please share links to the following to simplify understanding of your problem:
Faceted Browser (FCT) Page – click on “permalink” to get the canonical page URL
SPARQL Query produced by the FCT page – click on “SPARQL” top get that, then share the URL
My suspicion is that the UI is cloaking the effects of multiple named graphs that are used to construct the default graph used to produce the solution.
And here is the SPARQL text received from FCT by the live PoC:
HTTP/1.1 200 OK
Server: nginx/1.14.0 (Ubuntu)
Date: Wed, 27 Feb 2019 17:27:47 GMT
Content-Type: text/xml; charset=UTF-8
Connection: close
X-Powered-By: Express
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept
accept-ranges: bytes
Content-Length: 8703
filter (?s1 = <http://xmlns.com/foaf/0.1/Person>) .<fct:facets xmlns:fct="http://openlinksw.com/services/facets/1.0/">
<fct:sparql> select ?s1 as ?c1 count (*) as ?c2 where { select distinct ?s1 ?g {?s1 a <http://www.w3.org/2002/07/owl#Class> . quad map virtrdf:DefaultQuadMap { graph ?g { ?s1 ?s1textp ?o1 . ?o1 bif:contains '"Person"' . } } } } group by ?s1 order by desc 2 limit 30 offset 0 </fct:sparql>
<fct:time>1022</fct:time>
<fct:complete>yes</fct:complete>
<fct:timeout>14260</fct:timeout>
...
Ignoring the malformed xml (which I think it implying the problem, i.e. the filter is not being included/applied to the query), the two SPARQL queries are not equal in syntax. But the criteria are the same for both, e.g. search all fields for text 'Person', rdf:type == owl:Class, and subject IRI == foaf:Person.
Okay, what is the version of the FCT package installed? You more than likely need a later VAD, assuming you obtained yours from our download service.
The footer section of any FCT page reveals the version in use. Thus, if yours differs from a system that doesn’t exhibit these issues then you will need to upgrade.
Also, sometimes the Virtuoso instance at data.vios.network goes down and needs to be restarted. If you receive a bad response, please check if data.vios.network is up. I can restart it if it is down.
do we know what is the reason Virtuoso server to go down?
No, I don’t know why. Virtuoso spontaneously gives the message “The site is currently down for maintenance”. Sometimes restarting Virtuoso instance solves it, and sometimes the shutdown ends with error and the physical server has to be restarted.