research meeting
DESCRIPTION
Research Meeting. 2009-12-10 Jaeseok Myung. Summary. TA DB: grading , final exam ( 12/14) WEC: project(avg. 14.2/20), final exam (12/16, 301-421, 감독 ) 학부생논문지도 이승재 ( 기업인턴보고서 ), 김홍찬 (CF 기법을 웹 광고에 활용 ) 제출기한 : 12/24 Research SPARQL BGP Processing with Iterative MR - PowerPoint PPT PresentationTRANSCRIPT
Research Meeting
2009-12-10
Jaeseok Myung
Copyright 2009 by CEBT
Summary
TA
DB: grading, final exam (12/14)
WEC: project(avg. 14.2/20), final exam (12/16, 301-421, 감독 )
학부생논문지도 이승재 ( 기업인턴보고서 ), 김홍찬 (CF 기법을 웹 광고에 활용 )
제출기한 : 12/24
Research
SPARQL BGP Processing with Iterative MR
– Using finer keys for map tasks => Scailability
– Using advanced storage for selection task => Performance
– Using selectivity for BGP analysis
– Using MR pipelining
Application - Keyword Search over RDF Graphs
– Top-k Exploration of Query Candidates for Efficient Keyword Search on Graph-Shaped (RDF) Data, ICDE 2009
Center for E-Business Technology
Copyright 2009 by CEBT
Using Advanced Storage for Selection Task
Triple Indexing
SP-O
SO-P
PS-O
PO-S
OS-P
OP-S
S-PO
P-SO
O-SP
Center for E-Business Technology
Jaeseok MemberOf ?X
Jaeseok ?x IDS
Jaeseok ?x ?y
BigTable P P
S O O
S O O
S O O
S O O
BigTable O O
P S S
P S S
P S S
P S S
BigTable S S
O P P
O P P
O P P
O P P
.
.
.
.
.
.
Copyright 2009 by CEBT
Optimization for Selection Task
Implementation
Using Hadoop – HBase
Adding Data Loader Component
– N-Triple => HBase
Implementation of Selection Tasks using HBase
Comparison between N-Triple and Hbase
Center for E-Business Technology
Copyright 2009 by CEBT
Complex Query: Is It a Real-world Problem?
Users rarely make a complex query which contains a significant number of self-join
Actors who are married to each other and born in the same place
select distinct ?a ?b ?lat ?long where {?a dbpedia:spouse ?b.?a dbpedia:wikilink dbpediares:actor.?b dbpedia:wikilink dbpediares:actor.?a dbpedia:placeOfBirth ?c.?b dbpedia:placeOfBirth ?c.?c owl:sameAs ?c2.?c2 pos:lat ?lat.?c2 pos:long ?long.
}
For casual users, it is hard to know the underlying structure of RDF graphs
Center for E-Business Technology
?a ?b
?c
?c2
?lat ?long
actor
Copyright 2009 by CEBT
Keyword Query => SPARQL BGP
Top-k Exploration of Query Candidates for Efficient Key-word Search on Graph-Shaped (RDF) Data, ICDE 2009
Center for E-Business Technology
Copyright 2009 by CEBT
Complex Query: Real-world Problem
For keyword search, a significant number of iteration must be needed
Issue
Do we need to implement a module for translating a key-word query to a SPARQL query?
Center for E-Business Technology