Pratical Queries For Working With LSQ
For reference, here is a depicition of the LSQ data model 
# Get all SELECT queries from DBpedia log
SELECT DISTINCT ?text from <http://lsq.aksw.org/dbpedia> WHERE
{
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasSpin> ?spin .
?spin a <http://spinrdf.org/sp#Select> .
}
# Get all SELECT queries from Semantic Web Dog Food along with timestamps (the original execution time on the endpoint)
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
PREFIX prov: <http://www.w3.org/ns/prov#>
PREFIX sd: <http://www.w3.org/ns/sparql-service-description#>
SELECT Distinct ?text ?timeStamp From <http://lsq.aksw.org/swdf>
WHERE
{
?query lsqv:text ?text .
?query lsqv:hasRemoteExec ?re .
?re prov:atTime ?timeStamp .
?query lsqv:hasSpin ?spin .
?spin a <http://spinrdf.org/sp#Select> .
}
# Get all queries having resultset greater than zero.
SELECT DISTINCT ?text WHERE
{
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasRemoteExec> ?re .
?s <http://lsq.aksw.org/vocab#hasLocalExec> ?le .
?le <http://lsq.aksw.org/vocab#hasQueryExec> ?qe .
?qe <http://lsq.aksw.org/vocab#resultCount> ?rs .
FILTER(?rs > 0)
}
# Get all star shaped queries (There are four types of nodes in LSQ namely Star, Path, Hybrid, Sink).
SELECT DISTINCT ?text
WHERE
{
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasStructuralFeatures> ?sf .
?sf <http://lsq.aksw.org/vocab#hasBgp> ?bgp .
?bgp <http://lsq.aksw.org/vocab#hasBgpNode> ?jv .
?jv <http://lsq.aksw.org/vocab#joinVertexType> <http://lsq.aksw.org/vocab#star>.
}
# Queries along with their resultset sizes and runtimes
SELECT ?text ?rs ?sec
WHERE {
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasLocalExec> ?le .
?s <http://lsq.aksw.org/vocab#hasRemoteExec> ?re .
?le <http://lsq.aksw.org/vocab#hasQueryExec> ?qe .
?qe <http://lsq.aksw.org/vocab#resultCount> ?rs.
?qe <http://lsq.aksw.org/vocab#evalDuration> ?sec
}
# Queries with number of triple patterns
SELECT ?text ?tp
WHERE { ?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasStructuralFeatures> ?sf .
?sf <http://lsq.aksw.org/vocab#tpCount> ?tp.
}
# Queries and their number of join vertices.
SELECT ?text ?jv
WHERE
{
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasStructuralFeatures> ?sf .
?sf <http://lsq.aksw.org/vocab#joinVertexCount> ?jv.
}
# Total queries having Filters
SELECT (count(DISTINCT ?text) as ?totalFilter)
WHERE {
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasStructuralFeatures> ?sf .
?sf <http://lsq.aksw.org/vocab#usesFeature> <http://lsq.aksw.org/vocab#Filter> .
}
# Total queries having Solution modifiers
SELECT (count(DISTINCT ?text) as ?totalMod)
WHERE {
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasStructuralFeatures> ?sf .
?sf <http://lsq.aksw.org/vocab#usesFeature> ?uf .
FILTER(?uf = <http://lsq.aksw.org/vocab#OrderBy> || ?uf = <http://lsq.aksw.org/vocab#Offset> || ?uf = <http://lsq.aksw.org/vocab#Limit>)
}
# Total queries having SPARQL functions
SELECT (count(DISTINCT ?text) as ?totalFunc)
WHERE {
?s <http://lsq.aksw.org/vocab#text> ?text .
?s <http://lsq.aksw.org/vocab#hasStructuralFeatures> ?sf .
?sf <http://lsq.aksw.org/vocab#usesFeature> <http://lsq.aksw.org/vocab#Functions>
}
# Count of property paths
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
SELECT ?o (COUNT(*) AS ?ppathCount)
{
?s lsqv:usesFeature ?o .
FILTER(?o IN (lsqv:LinkPath, lsqv:ReverseLinkPath, lsqv:NegPropSetPath , lsqv:InversePath, lsqv:ModPath, lsqv:FixedLengthPath, lsqv:DistinctPath, lsqv:MultiPath, lsqv:ShortestPath, lsqv:ZeroOrOnePath)) } GROUP BY ?o ORDER BY DESC(COUNT(*)
)
# Top objects ordered by query count
SELECT ?object COUNT(Distinct ?query) as ?queryCount
{
?s <http://lsq.aksw.org/vocab#text> ?query .
?s <http://lsq.aksw.org/vocab#hasStructuralFeatures> ?sf .
?sf <http://lsq.aksw.org/vocab#hasTP> ?tp .
?tp <http://spinrdf.org/sp#object> ?object
}
GROUP BY ?object
ORDER BY DESC(?queryCount)
# Various features of SPARQL queries
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
SELECT DISTINCT ?qId ?joinVertices ?tps ?rs ?rt ?meanJoinVertexDegree
{
?qId lsqv:text ?text .
?qId lsqv:hasRemoteExec ?re .
?qId lsqv:hasLocalExec ?le .
?qId lsqv:hasStructuralFeatures ?sf .
?sf lsqv:projectVarCount ?projVars.
?sf lsqv:joinVertexCount ?joinVertices .
?sf lsqv:tpCount ?tps .
?sf lsqv:joinVertexDegreeMean ?meanJoinVertexDegree .
?sf lsqv:usesFeature lsq:Select .
?le lsqv:hasQueryExec ?qe .
?qe lsqv:resultCount ?rs.
?qe lsqv:evalDuration ?rt.
FILTER (?rs > 0 && ?rs < 20000000 && ?tps > 0)
}
LIMIT 1000000
# find queries with dbo:Actor as an object in a triple pattern
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
PREFIX sp: <http://spinrdf.org/sp#>
SELECT DISTINCT ?text ?query
WHERE {
?query lsqv:text ?text .
?query lsqv:hasStructuralFeatures/lsqv:hasBgp/lsqv:hasTpInBgp/lsqv:hasTp/sp:object dbo:Actor .
}
# find queries with the actor keyword
PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
PREFIX sp: <http://spinrdf.org/sp#>
SELECT DISTINCT ?text ?query
WHERE {
?query lsqv:text ?text .
?text bif:contains "actor" .
}
The following result sets of SPARQL queries are based on the LSQ output of this query:
PREFIX swc: <http://data.semanticweb.org/ns/swc/ontology#>
SELECT * {
?obj a swc:SessionEvent ;
?prop ?target
}
Querying The Static Structure
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT ?bgpLabel ?bgpNodeLabel ?subBgpLabel ?subTpLabel {
?query lsq:hasStructuralFeatures ?sf .
?sf lsqv:hasBgp ?bgp .
?bgp lsqv:hasBgpNode ?bgpNode .
?bgpNode lsqv:hasSubBgp ?subBgp .
?subBgp lsqv:hasTpInBgp ?subTpInBgp .
?subTpInBgp lsqv:hasTp ?subTp .
?bgp rdfs:label ?bgpLabel .
?bgpNode rdfs:label ?bgpNodeLabel .
?subBgp rdfs:label ?subBgpLabel .
?subTp rdfs:label ?subTpLabel .
} ORDER BY ?bgpLabel ?bgpNodeLabel ?subBgpLabel ?subTpLabel
Accessing the RDF terms and variables of a query’s triple patterns (via the BGPs)
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
PREFIX sp: <http://spinrdf.org/sp#>
SELECT ?tpLabel ?s ?p ?o {
{ SELECT * { ?query lsqv:hasStructuralFeatures ?sf } LIMIT 1 }
Graph ?g {
?sf lsqv:hasBgp ?bgp .
?bgp lsqv:hasTpInBgp ?tpInBgp .
?tpInBgp lsqv:hasTp ?tp .
?bgp rdfs:label ?bgpLabel .
?tp rdfs:label ?tpLabel .
?tp sp:subject ?s .
?tp sp:predicate ?p .
?tp sp:object ?o .
}
}
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| bgpLabel | bgpNodeLabel | subBgpLabel | subTpLabel |
==============================================================================================================================================================================================================================================================================================================================================
| "?obj a <http://data.semanticweb.org/ns/swc/ontology#SessionEvent> ;\n ?prop ?target" | "?obj" | "?obj a <http://data.semanticweb.org/ns/swc/ontology#SessionEvent> ;\n ?prop ?target" | "?obj <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://data.semanticweb.org/ns/swc/ontology#SessionEvent>" |
| "?obj a <http://data.semanticweb.org/ns/swc/ontology#SessionEvent> ;\n ?prop ?target" | "?obj" | "?obj a <http://data.semanticweb.org/ns/swc/ontology#SessionEvent> ;\n ?prop ?target" | "?obj ?prop ?target" |
| "?obj a <http://data.semanticweb.org/ns/swc/ontology#SessionEvent> ;\n ?prop ?target" | "?prop" | "?obj ?prop ?target" | "?obj ?prop ?target" |
| "?obj a <http://data.semanticweb.org/ns/swc/ontology#SessionEvent> ;\n ?prop ?target" | "?target" | "?obj ?prop ?target" | "?obj ?prop ?target" |
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Querying Over Executions
The following elements of SPARQL queries are evaluated in benchmark runs which in essence leads to statistical observations w.r.t. those elements. The affected elements are: bgp, tpInBgp, tp and bgpNode.
The query is admittedly quite large but the essence is that from a given execution of a query (via lsq:hasLocalExec) all corresponding executions of that query’s constituent elements are unambiguously accessible. Each execution is linked to the appropriate element via lsq:hasExec in reverse direction. Note, that the rationale for the reverse link is that from an element all corresponding executions are reachable via forward links which is aimed at providing nicer Linked Data views.
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT ?exp ?bgpLabel ?bgpNodeLabel ?subBgpLabel ?subTpLabel ?bgpSize ?subTpSize ?subTpToBgpRatio {
?query lsqv:hasLocalExec ?localExec .
?localExec lsqv:hasBgpExec ?bgpExec .
?bgpExec lsqv:hasJoinVarExec ?bgpNodeExec .
?bgpNodeExec lsqv:hasSubBgpExec ?subBgpExec .
?subBgpExec lsqv:hasTpInBgpExec ?subTpInBgpExec .
?subTpInBgpExec lsqv:hasTpExec ?subTpExec .
# Links from the executions to the query's elements
?bgp lsqv:hasExec ?bgpExec ; rdfs:label ?bgpLabel .
?bgpNode lsqv:hasExec ?bgpNodeExec ; rdfs:label ?bgpNodeLabel .
?subBgp lsqv:hasExec ?subBgpExec ; rdfs:label ?subBgpLabel .
?subTp lsqv:hasExec ?subTpExec ; rdfs:label ?subTpLabel .
?localExec lsqv:benchmarkRun ?exp .
# Get the measurements
?subBgpExec lsqv:hasElementExec [ lsqv:resultCount ?bgpSize ] .
?subTpExec lsqv:hasElementExec [ lsqv:resultCount ?subTpSize ] .
?subTpInBgpExec lsqv:tpToBgpRatio ?subTpToBgpRatio .
# Further useful triple patterns
# ?query lsqv:hash ?queryHash .
# ?exp dct:identifier ?expId .
# bgp/tp selectivities (may be absent if involved result sets exceeded benchmark limits)
# OPTIONAL { ?subTpInBgpExec lsqv:bgpRestrictedTpSel ?bgpRestrictedTpSel }
} ORDER BY ?exp ?bgpLabel ?bgpNodeLabel ?subBgpLabel
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| exp | bgpLabel | bgpNodeLabel | subBgpLabel | subTpLabel | bgpSize | subTpSize | subTpToBgpRatio |
=========================================================================================================================================================================================================================================================================
| lsqr:xc-dbpedia.org-somedata_2020-07-25_at_05-08-2020_02:24:05 | "?obj a swc:SessionEvent ;\n ?prop ?target" | "?obj" | "?obj a swc:SessionEvent ;\n ?prop ?target" | "?obj a swc:SessionEvent" | 0 | 0 | 0 |
| lsqr:xc-dbpedia.org-somedata_2020-07-25_at_05-08-2020_02:24:05 | "?obj a swc:SessionEvent ;\n ?prop ?target" | "?obj" | "?obj a swc:SessionEvent ;\n ?prop ?target" | "?obj ?prop ?target" | 0 | 900 | 0 |
| lsqr:xc-dbpedia.org-somedata_2020-07-25_at_05-08-2020_02:24:05 | "?obj a swc:SessionEvent ;\n ?prop ?target" | "?prop" | "?obj ?prop ?target" | "?obj ?prop ?target" | 900 | 900 | 1 |
| lsqr:xc-dbpedia.org-somedata_2020-07-25_at_05-08-2020_02:24:05 | "?obj a swc:SessionEvent ;\n ?prop ?target" | "?target" | "?obj ?prop ?target" | "?obj ?prop ?target" | 900 | 900 | 1 |
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Find Sparse Join Candidates among BGPs
# Find Sparse join candidates: Search for basic graph patterns that have significantly
# fewer results than the smallest result set among its triple patterns.
PREFIX lsqv: <http://lsq.aksw.org/vocab#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT ?exp ?text ?bgpLabel ?bgpLabel ?bgpLabel ?tpLabel ?bgpSize ?tpSize ?bgpTpSizeRatio {
{ SELECT * { # Comment out this SELECT block to run this query on all data
{
?query lsqv:hasLocalExec ?localExec .
?localExec lsqv:hasBgpExec ?bgpExec .
# Links from the executions to the query's elements
?bgp lsqv:hasExec ?bgpExec ; rdfs:label ?bgpLabel .
?bgpExec lsqv:hasElementExec [ lsqv:resultCount ?bgpSize ] .
# Discard bgps with empty results
FILTER(?bgpSize > 0)
}
LATERAL {
# For the current bgpExec, get the tp with the smallest result set size
SELECT ?bgpExec ?tpExec ?tpSize {
?bgpExec lsqv:hasTpInBgpExec ?tpInBgpExec .
?tpInBgpExec lsqv:hasTpExec ?tpExec .
?tpExec lsqv:hasElementExec [ lsqv:resultCount ?tpSize ] .
} ORDER BY ASC(?tpSize) LIMIT 1
}
# Compute the ratio of the bgp size vs smallest tp size
BIND(?bgpSize / ?tpSize AS ?bgpTpSizeRatio)
?tp lsqv:hasExec ?tpExec ; rdfs:label ?tpLabel .
?localExec lsqv:benchmarkRun ?exp .
?query lsqv:text ?text
} LIMIT 1000 }
}
ORDER BY ASC(?bgpTpSizeRatio)
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| exp | bgpLabel | tpLabel | bgpSize | tpSize | bgpTpSizeRatio |
===========================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================================
| <http://lsq.aksw.org/xc-dbpedia_2020-10-10_at_10-10-2020_18:29:19> | "?id a <http://dbpedia.org/ontology/Film> ;\n <http://dbpedia.org/property/title> ?ft ;\n <http://dbpedia.org/ontology/imdbId> ?imdb_id" | "?id <http://dbpedia.org/ontology/imdbId> ?imdb_id" | "23"^^<http://www.w3.org/2001/XMLSchema#long> | "70876"^^<http://www.w3.org/2001/XMLSchema#long> | 0.000324510412551498391557 |
| <http://lsq.aksw.org/xc-dbpedia_2020-10-10_at_10-10-2020_18:29:19> | "?artist a <http://dbpedia.org/ontology/MusicalArtist> ;\n <http://www.w3.org/2000/01/rdf-schema#label> ?name ;\n <http://dbpedia.org/property/genre> <http://dbpedia.org/resource/Acid_rock> ;\n <http://dbpedia.org/property/genre> <http://dbpedia.org/resource/Funk_rock> ;\n <http://dbpedia.org/property/genre> <http://dbpedia.org/resource/Psychedelic_rock>" | "?artist <http://dbpedia.org/property/genre> <http://dbpedia.org/resource/Acid_rock>" | "1"^^<http://www.w3.org/2001/XMLSchema#long> | "356"^^<http://www.w3.org/2001/XMLSchema#long> | 0.002808988764044943820225 |
| <http://lsq.aksw.org/xc-dbpedia_2020-10-10_at_10-10-2020_18:29:19> | "?author a <http://dbpedia.org/ontology/Writer> .\n?film <http://dbpedia.org/ontology/writer> ?author .\n?actor <http://dbpedia.org/property/starring> ?film .\n?author <http://www.w3.org/2002/07/owl#sameAs> ?nytId" | "?author <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Writer>" | "116"^^<http://www.w3.org/2001/XMLSchema#long> | "30649"^^<http://www.w3.org/2001/XMLSchema#long> | 0.003784789063264706841985 |
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