SPARQL Extensions with Preferences: a Survey Olivier Pivert, Olfa Slama, Virginie Thion

Transcription

1 SPARQL Extensions with Preferences: a Survey Olivier Pivert, Olfa Slama, Virginie Thion 31 st ACM Symposium on Applied Computing Pisa, Italy April 4-8, 2016

2 Outline 1 Introduction 2 3 4

3 Outline Introduction 1 Introduction 2 RDF SPARQL 3 4 Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 3 / 24

4 Introduction RDF Boolean relationships. e.g. Friend (best, close, normal). SPARQL Boolean conditions. e.g. Age < 23 (young). Fuzzy extension of the RDF data model and SPARQL querying language (user preference queries). Preference query: I want to find a cheap hotel near the beach. Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 4 / 24

5 Outline Introduction RDF SPARQL 1 Introduction 2 RDF SPARQL 3 4 Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 5 / 24

6 RDF SPARQL RDF (Resource Description Framework) (W3C) RDF is a model for publishing (linked) data on the web. Subject Predicate object s, p, o : the subject s has a property p with a value o. Subject: the resource being described; Predicate: the property of the resource; Object: the property value. Ocean s Twelve movie:actor George Clooney Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 6 / 24

7 Movie:film The American Anton Corbijn movie:director_name resource/director/9742 dc:title movie:director rdf:type resource/film/97605 movie:writer dc:date movie:actor George Clooney movie:actor_name resource/actor/30516 Rowan Joffe movie:writer_name resource/writer/ dc:date movie:actor resource/film/5541 Figure: Sample RDF graph extracted from IMDb 1 1

8 RDF SPARQL SPARQL (SPARQL Protocol and RDF Query Language) (W3C) Query language for querying RDF data based on graph pattern matching. Graph pattern: set of triples patterns containing variables.?movie movie:actor?actor?actor movie:actor_name G.Clooney?Movie movie:actor movie:actor_name G.Clooney?Actor PREFIX.. #Prefix declarations SELECT.. #Result FROM.. #Dataset definition WHERE.. #Pattern ORDER BY.., DISTINCT.., LIMIT.., OFFSET.. #Modifiers Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 8 / 24

9 RDF SPARQL Example Q1: retrieve the names and the dates of the movies featuring George Clooney. PREFIX dc: < PREFIX movie: < SELECT?Name?Date WHERE {?Movie dc:title?name.?movie dc:date?date.?movie movie:actor?actor.?actor movie:actor_name "George Clooney". }?Name dc:title?movie movie:actor movie:actor_name?actor George Clooney?date dc:date Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 9 / 24

10 Outline Introduction 1 Introduction 2 RDF SPARQL 3 4 Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 10 / 24

11 Motivation Extend SPARQL by the integration of user preferences in queries. Goal Make SPARQL more flexible: is more faithful to what a user intends to say; rank-orders the retrieved items; provides a relaxed version of the query. Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 11 / 24

12 Motivation Extend SPARQL by the integration of user preferences in queries. 1 : preferences are expressed by a monotone scoring function. Fuzzy extensions [Cheng et al., 2010] Top-k-queries [Bozzon et al., 2012, Magliacane et al., 2012] 2 : preferences are defined through binary preference relations (Comedy Action Drama). Skyline queries [Siberski et al., 2006, Gueroussova et al., 2013] Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 12 / 24

13 Motivation Extend SPARQL by the integration of user preferences in queries. 1 : preferences are expressed by a monotone scoring function. Fuzzy extensions [Cheng et al., 2010] Top-k-queries [Bozzon et al., 2012, Magliacane et al., 2012] 2 : preferences are defined through binary preference relations (Comedy Action Drama). Skyline queries [Siberski et al., 2006, Gueroussova et al., 2013] Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 13 / 24

14 Fuzzy extensions of SPARQL f-sparql [Cheng et al., 2010] Based on fuzzy set theory [Zadeh, 1965]. gradual condition satisfaction degree in [0..1]. Supports the expression of fuzzy terms, e.g. recent µ recent year Extends the syntax of SPARQL. SELECT... WHERE {... FILTER (?X = FT) [WITH α]} Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 14 / 24

15 Q2: retrieve recent movies with George Clooney. SELECT?Name?Date WHERE {?Movie dc:title?name.?movie dc:date?date.?movie movie:actor?actor.?actor movie:actor_name "George Clooney". FILTER (?Date = recent).} Q3: retrieve the recent (importance 0.2) movies featuring George Clooney with a high rating (importance 0.8). SELECT?Name?Date?Rating WHERE {...?Movie dc:rate?rating. FILTER (?Date = recent) WITH 0.2. (?Rating = high) WITH 0.8.} Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 15 / 24

16 Motivation Extend SPARQL by the integration of user preferences in queries. 1 : preferences are expressed by a monotone scoring function. Fuzzy extensions[cheng et al., 2010] Top-k-queries [Bozzon et al., 2012, Magliacane et al., 2012] 2 : preferences are defined through binary preference relations. Skyline queries [Siberski et al., 2006, Gueroussova et al., 2013] Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 16 / 24

17 Top-k-Queries [Bruno et al., 2002] return only the k most relevant tuples according to user s preferences. Materialize then sort procedure Q4: find the best 5 offers of movies ordered by a function of user ratings and date. SELECT?Movie?Offer (g 1 (?avgrating) + g 2 (?date1) AS?score) WHERE {?Offer type:movie?movie?movie hasavgrating?avgrating.?movie dc:title?name.?movie dc:date?date1.} ORDER BY DESC(?score)LIMIT 5 SPARQLRank algebra [Bozzon et al., 2012, Magliacane et al., 2012]: speeds up the execution of top-k queries in SPARQL. Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 17 / 24

18 Motivation Extend SPARQL by the integration of user preferences in queries. 1 : preferences are expressed by a monotone scoring function. Fuzzy extensions [Cheng et al., 2010] Top-k-queries [Bozzon et al., 2012, Magliacane et al., 2012] 2 : preferences are defined through binary preference relations (Comedy Action Drama). Skyline queries [Siberski et al., 2006, Gueroussova et al., 2013] Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 18 / 24

19 Skyline queries [Borzsony et al., 2001] Filter an n-dimensional dataset and return only the tuples that are not dominated in the sense of Pareto order. Tuple t Pareto dominates tuple t (t t ), iff t: 1 is at least good as t in all dimensions: i {1,..., n}, t i i t i, 2 and strictly better in at least one dimension: j {1,..., n}, t j j t j. Criteria: preferring recent and high rated movie. Movie date rating M M M Skyline result: {M 1, M 3 }. Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 19 / 24

20 Skyline queries [Siberski et al., 2006, Gueroussova et al., 2013] SPARQL with a preferring clause supporting multidimensional preferences. Q5: prefer the movies rated excellent over very good ones and the movies whose projection time is between 3pm and 11pm. SELECT... WHERE {... FILTER (?rating = ft:excellent?rating = ft:very-good) PREFERRING?rating = ft:excellent AND (?ProjectionStarts >= 3pm?ProjectionEnds <= 11pm)} PrefSPARQL: supports conditional preferences (if-then-else). Q6: prefer watching a movie after 7:30pm on the weekdays and before 7pm during the weekends SELECT... WHERE {... PREFERRING(if (?D = Saturday?D = Sunday ) then?projs < 7pm else?projs >= 7:30pm)} Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 20 / 24

21 Outline Introduction 1 Introduction 2 RDF SPARQL 3 4 Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 21 / 24

22 Approach [Cheng et al., 2010] [Wang et al., 2012] [Bozzon et al., 2012] [Magliacane et al., 2012] [Dividino et al., 2012] [Siberski et al., 2006] [Gueroussova et al., 2013] [Chen et al., 2011] SPARQL extension [Buche et al., 2008] [Cedeño and Candan, 2011] Preference queries Type Ranking Weighted graph Fuzzy Total order Top-k Total order Skyline Partial order Fuzzy Total order Fuzzy annotations Top-k Partial order Weighted edges Querying weighted RDF data (i.e., intensity...). e.g: A user strongly recommends a movie (degree 0.8) Preferences on the structure of the graph. e.g: Find the shortest path between friends who have liked much the same album

23 Future work We are currently defining a fuzzy extension of the SPARQL language to weighted RDF graph: 1 query a fuzzy RDF data model where relations are gradual. - [Mazzieri and Dragoni, 2008], [Straccia, 2009],... 2 express fuzzy user preferences queries: on data (fuzzy conditions); and on the structure of the data graph (fuzzy regular expressions). - [Pivert et al., 2014]: Fuzzy graph DB using fuzzy CYPHER. - [Alkhateeb et al., 2009], [Pérez et al., 2008]: regular expressions in SPARQL. First step: [Olivier Pivert, Olfa Slama, Virginie Thion, FUZZ-IEEE, Vancouver, CANADA, JULY 24-29, 2016] Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 23 / 24

24 Thank you for your attention Questions?

25 Alkhateeb, F., Baget, J., and Euzenat, J. (2009). Extending SPARQL with regular expression patterns (for querying RDF). J. Web Sem., 7(2): Borzsony, S., Kossmann, D., and Stocker, K. (2001). The skyline operator. In Proc. of ICDE, pages Bozzon, A., Della Valle, E., and Magliacane, S. (2012). Extending SPARQL Algebra to Support Efficient Evaluation of Top-K SPARQL Queries. In Search Computing, volume 7538, pages Bruno, N., Chaudhuri, S., and Gravano, L. (2002). Top-k selection queries over relational databases: Mapping strategies and performance evaluation. Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 24 / 24

26 ACM Trans. on Database Syst., 27(2): Buche, P., Dibie-Barthélemy, J., and Hignette, G. (2008). Flexible querying of fuzzy RDF annotations using fuzzy conceptual graphs. In Proc. of ICCS, pages Cedeño, J. P. and Candan, K. S. (2011). R2DF Framework for Ranked Path Queries over Weighted RDF Graphs. In Proc. of WIMS, pages 40:1 40:12. Chen, L., Gao, S., and Anyanwu, K. (2011). Efficiently evaluating skyline queries on RDF databases. In Proc. of the Intl. Conf. on Extended Sem. Web Conference (ESWC), pages Cheng, J., Ma, Z., and Yan, L. (2010). Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 24 / 24

27 f-sparql: a flexible extension of SPARQL. In Proc. of DEXA, pages Dividino, R., Gröner, G., Scheglmann, S., and Thimm, M. (2012). Ranking RDF with provenance via preference aggregation. In Proc. of EKAW, pages Gueroussova, M., Polleres, A., and McIlraith, S. A. (2013). SPARQL with qualitative and quantitative preferences. In Proc. of the Intl. Workshop OrdRing, co-located with ISWC, pages 2 8. Magliacane, S., Bozzon, A., and Della Valle, E. (2012). Efficient Execution of Top-K SPARQL Queries. In Proc. of ISWC, pages Mazzieri, M. and Dragoni, A. F. (2008). Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 24 / 24

28 A fuzzy semantics for the resource description framework. Springer. Pérez, J., Arenas, M., and Gutierrez, C. (2008). nsparql: A navigational language for RDF. In Proc. of ISWC. Pivert, O., Thion, V., Jaudoin, H., and Smits, G. (2014). On a fuzzy algebra for querying graph databases. In Proc. of IEEE ICTAI, pages Siberski, W., Pan, J. Z., and Thaden, U. (2006). Querying the Semantic Web with Preferences. In Proc. of ISWC, pages Straccia, U. (2009). A minimal deductive system for general fuzzy RDF. Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 24 / 24

29 In Web Reasoning and Rule Syst., pages Springer. Wang, H., Ma, Z., and Cheng, J. (2012). fp-sparql: an RDF fuzzy retrieval mechanism supporting user preference. In Proc. of FSKD, pages Zadeh, L. A. (1965). Fuzzy sets. Info. and control, 8(3): Olivier Pivert, Olfa Slama, Virginie Thion SPARQL Extensions with Preferences: a Survey 24 / 24