FCT aggregates and filters

sparql
fct

#21

It may be an idea to kill with -11 the process to get core dump
or to attach with gdb and do ‘thread apply all where’


#22

Got it, thanks. I will try this to help with troubleshooting.


#23

@imitko

The LOD instance does not show symptoms of the filter bug. Is it possible to send the FCT VAD running at LOD? The filter bug is best exemplified in these two queries:

DBPedia (this instance is affected)
LOD (this instance is not affected)

Here are the two responses:

DBPedia Response (mal-formed)

HTTP/1.1 200 OK
Server: nginx/1.14.0 (Ubuntu)
Date: Sun, 10 Mar 2019 03:31:12 GMT
Content-Type: text/xml; charset=UTF-8
Connection: close
X-Powered-By: Express
access-control-allow-origin: *
access-control-allow-headers: Depth,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Accept-Encoding
vary: Accept-Encoding
access-control-allow-credentials: true
access-control-allow-methods: GET, POST, OPTIONS
Content-Length: 7752

 filter (?s1 = <http://dbpedia.org/resource/Bay_of_Kotor>) .<fct:facets xmlns:fct="http://openlinksw.com/services/facets/1.0/">
<fct:sparql>     select ?s1p as ?c1 count (*) as ?c2  where  {?s1 a &lt;http://dbpedia.org/class/yago/BodyOfWater109225146&gt; . quad map virtrdf:DefaultQuadMap { graph ?g {  ?s1 ?s1textp ?o1 . ?o1 bif:contains  &#39;&quot;sea&quot;&#39;  . } }  ?s1 &lt;http://dbpedia.org/property/year&gt; ?s2 . ?s1 ?s1p ?s1o . } group by ?s1p order by desc 2 limit 30  offset 0 </fct:sparql>
<fct:time>955</fct:time>
<fct:complete>yes</fct:complete>
<fct:timeout>13560</fct:timeout>

LOD Response (well-formed)

HTTP/1.1 200 OK
Server: nginx/1.14.0 (Ubuntu)
Date: Sun, 10 Mar 2019 03:31:38 GMT
Content-Type: text/xml; charset=UTF-8
Content-Length: 8113
Connection: close
X-Powered-By: Express
access-control-allow-origin: *
access-control-allow-headers: DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Accept-Encoding
accept-ranges: bytes
access-control-allow-credentials: true
access-control-allow-methods: GET, POST, OPTIONS

<fct:facets xmlns:fct="http://openlinksw.com/services/facets/1.0/">
<fct:sparql>     select ?s1p as ?c1 count (*) as ?c2  where  {?s1 a &lt;http://dbpedia.org/class/yago/BodyOfWater109225146&gt; .  quad map virtrdf:DefaultQuadMap { graph ?g {  ?s1 ?s1textp ?o1 . ?o1 bif:contains  &#39;&quot;sea&quot;&#39;  . }}  quad map virtrdf:DefaultQuadMap { ?s1 &lt;http://dbpedia.org/property/year&gt; ?s2 . } filter (?s1 = &lt;http://dbpedia.org/resource/Bay_of_Kotor&gt;) . ?s1 ?s1p ?s1o . } group by ?s1p order by desc 2 limit 30  offset 0 </fct:sparql>
<fct:time>96</fct:time>
<fct:complete>yes</fct:complete>
<fct:timeout>13560</fct:timeout>

#24

The LOD instance exhibits the filter bug symptoms now also. This query returns mal-formed XML.

HTTP/1.1 200 OK
Server: nginx/1.14.0 (Ubuntu)
Date: Tue, 12 Mar 2019 21:26:46 GMT
Content-Type: text/xml; charset=UTF-8
Connection: close
X-Powered-By: Express
access-control-allow-origin: *
access-control-allow-headers: Depth,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Accept-Encoding
vary: Accept-Encoding
access-control-allow-credentials: true
access-control-allow-methods: GET, POST, OPTIONS
Content-Length: 3412

 filter (?s5 = <http://dbpedia.org/resource/Orson_Welles>) .<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 &lt;http://dbpedia.org/class/yago/WikicatBlack-and-whiteFilms&gt; .?s1 a &lt;http://dbpedia.org/class/yago/WikicatDystopianFilms&gt; . ?s1 &lt;http://dbpedia.org/ontology/producer&gt; ?s2 . ?s1 &lt;http://dbpedia.org/ontology/distributor&gt; ?s3 . ?s1 &lt;http://dbpedia.org/ontology/director&gt; ?s4 . ?s1 &lt;http://dbpedia.org/ontology/starring&gt; ?s5 . } } group by ?s1 order by desc 2 limit 15  offset 0 </fct:sparql>
<fct:time>77</fct:time>

Note, this was not the case a couple of weeks ago.


#25

The below SPARQL query does not return the appropriate results. The subject ?s1 should have “STAR WARS” in its rdfs:label, but some of the results do not:

select distinct ?s1 as ?c1 ?o1 ?g where  { 

quad map virtrdf:DefaultQuadMap { 
  graph ?g {  
  ?s1 <http://www.w3.org/2000/01/rdf-schema#label> ?o1 . 
  ?o1 bif:contains  '(STAR AND WARS)'  . 
}}  

quad map virtrdf:DefaultQuadMap { 
  ?s1 <http://purl.org/dc/terms/subject> ?s2 . 
} 

optional { graph virtrdf:IRI_Rank_c {  
  ?s1 virtrdf:IRI_Rank_rnk_c_int ?srank1 . 
} }  

quad map virtrdf:DefaultQuadMap { ?s1 <http://purl.org/dc/terms/subject> ?s3 . } 

filter (?s3 = <http://dbpedia.org/resource/Category:Game_Boy_Advance_games>) . 

} 

order by desc (?srank1)