1. Querying the RDF: Small Case Study in the Bicycle Sale Domain Ondřej Šváb, Vojtěch Svátek, Martin Kavalec, Martin Labský VŠE, University of Economics, Prague

2. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 2 Content 1. Integration of web analytic tools 2. RDF/S 3. Bicycle Sale Domain in RDF/S 4. Sesame 5. RDF query languages 6. Example of HTML interface usage

3. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 3 1. Integration of web analytic tools Analytic tools from RAINBOW http://rainbow.vse.cz

4. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 4

5. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 5 2. RDF/S RDF – Resource description framework –Assertional language for information representation –Reification –RDF graph –Several types of serialization: RDF/XML, N-Triples, N3 RDFS – Resource description framework schema –Semantic language for RDF –„core vocabulary“, enables to define properties, classes and their taxonomy (hierarchy)

6. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 6 3. Bicycle Sale Domain in RDF/S Typical extracted attributes: –Name of bike, price, picture, components Giant Terrago F/S 3 350.00

7. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 7

8. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 8

9. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 9

10. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 10 Example of reification

11. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 11

12. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 12 4. Sesame System for manipulating with RDF/S –http://www.openrdf.org Four functional modules: –Query Module –Admin Module –Extract Module –Explore Module

13. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 13

14. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 14 5. RDF query languages RDQL –Implemented according to HP specification RQL –Original proposal by ICS-FORTH SeRQL –Developed as part of system Sesame

15. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 15 Pros/ConsRDQLRQLSeRQL Path expr.+++ RDFS support -+++ Optional path exp. -+++ Reified statements ++++ Strings comp. -++ Features of RDF query languages

16. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 16 Path expressions:

17. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 17 Namespaces in queries using namespace web =, xsd =, bike =, comp =, meta =, pict =, rdfs =, rdf =

18. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 18 RQL/SeRQL 1 RQL select domain(@predicate), @predicate, range(@predicate) from {} @predicate {} where @predicate = pict:hasWidth SeRQL select domain, range from { } {domain}, { } {range} 1Q: Find restrictions (domain and range) of property hasWidth.

19. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 19 RQL/SeRQL 2 RQL select X, name, picture, width from {X : bike:RetailOffer } bike:hasName {name}, {X} bike:hasPicture {picture}. pict:hasWidth {width} where name like "l*" and width < 70 2Q: Find all retail offers with name starting with letter ”l” and having a picture with width lower than 70. SeRQL select X, name, picture, width from {X} { }, {X} {name}, {X} {Y} {width} where name like "l*" and width

20. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 20 RQL 3/1 3Q: Find all retail offers of bicycles that have a concrete bike component. Output the name of company that offers the bike, the picture of retail offer, the price of bike (offer). Retrieve the retail offer even if the URL of picture is not known. (select web, company, price, picture, name from {X : bike:RetailOffer } bike:hasCompany {web : comp:Company }. comp:companyName {company}, {X} bike:hasPrice {price}, {X} bike:hasPicture {picture}, {X} bike:hasBikeProduct {idtyp}. bike:name {name} where idtyp=data:part1 ) Union …

21. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 21 … Union (select web, company, price, null, name from {X : bike:RetailOffer } bike:hasCompany {web : comp:Company }. comp:companyName {company}, {X} bike:hasPrice {price}, {X} bike:hasBikeProduct {idtyp}. bike:name {name} where idtyp=data:part1 and not (X in select X from {X} bike:hasPicture {picture})) RQL 3/2 Operator “in” - subquery Result = S1un. S2

22. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 22 SeRQL 3 select prv, web, company, price, picture, name from {prv} { }; {price}; [ {picture}]; {idtyp}, {idtyp} {name}, {prv} {web} { }; {company} where idtyp =

23. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 23 RQL 4 – query over reified statements select X, obj, certainty from {X : rdf:Statement } rdf:subject {reifSubj}, {X} rdf:predicate {reifPred}, {X} rdf:object {reifObj}, {X} meta:hasMeta {obj}. meta:certainty {certainty} where certainty > "0.9" 4Q: Find all statements that have certainty higher than 0.9.

24. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 24 SeRQL 4 –query reified statements select obj, certainty from { {reifSubj} reifPred {reifObj} } {obj} {certainty} where certainty > "0.9"^^

25. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 25 6. Example of HTML interface (usage) -Three parts -First for specifying the query -Second for result -Third for „detailed“ results in certain regard

26. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 26 HTML interface

27. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 27 Initial query

28. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 28 Following query – [About]

29. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 29 Following query – [Picture]

30. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 30

31. Dateso 04 Querying the RDF: Small Case Study in the Bicycle Sale Domain 31 Future work –Integration, transformation –More active cooperation with Sesame –HTML interface and better querying –Testing with greater amount of real-world data

32. Thank you for your attention