Creating Linked Data from Relational Databases

  • Nikolaos Konstantinou
  • Dimitrios-Emmanuel Spanos


In this Chapter, we consider relational databases as a data source for the generation of Linked Data, given that they constitute one of the most popular data storage media, containing huge data volumes that feed the vast majority of information systems worldwide. In this context, we review the related literature and reveal the main motivations that fuel the relevant approaches, and the benefits that arise from their application. We present a categorization of approaches that map relational databases to the Semantic Web and identify tool implementations that extract RDF graphs from relational database instances. We also sketch a proof-of-concept use case scenario regarding how a repository with scholarly information can be converted to a Linked Data endpoint. The Chapter ends with a discussion of the open issues and future outlook for the problem of RDF generation from relational databases.


Relational Database Link Data Domain Ontology Database Schema SPARQL Query 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. An Y, Borgida A, Mylopoulos J (2006) Discovering the semantics of relational tables through mappings. J Data Semantics 7:1–32Google Scholar
  2. An Y, Borgida A, Miller RJ et al (2007) A semantic approach to discovering schema mapping expressions. In: Chirkova R, Oria V (eds) Proceedings of 2007 IEEE 23rd international conference on data engineering (ICDE 2007), Istanbul, Turkey, April 2007. IEEE, pp 206–215Google Scholar
  3. An Y, Hu X, Song IY (2008) Round-trip engineering for maintaining conceptual-relational mappings. In: Bellahsène Z, Léonard M (eds) Advanced information systems engineering: 20th international conference (CAiSE 2008), Montpellier, France, June 2008. Lecture notes in computer science, vol. 5074. Springer, Heidelberg, pp 296–311Google Scholar
  4. Auer S, Dietzold S, Lehmann J et al (2009) Triplify—Light-weight linked data publication from relational databases. In: WWW’09, Proceedings of the 18th international conference on World Wide Web, New York, NY, USA, pp 621–630Google Scholar
  5. Barrasa J, Corcho O, Gómez-Pérez A (2004) R2O, an extensible and semantically based database-to-ontology mapping language. Second international workshop on semantic web and databases (SWDB 2004), 29–30 August 2004, Toronto, CanadaGoogle Scholar
  6. Barrasa-Rodriguez J, Gómez-Pérez A (2006) Upgrading relational legacy data to the semantic web. In: WWW’06, Proceedings of the 15th international conference on World Wide Web, Edinburgh, Scotland, April 2006. ACM, New York, pp 1069–1070Google Scholar
  7. Beckett D, Grant J (2003) SWAD-Europe Deliverable 10.2: mapping semantic web data with RDBMSes. Accessed 26 Dec 2014
  8. Ben Necib C, Freytag JC (2005) Semantic query transformation using ontologies. In: Desai BC, Vossen G (eds) Proceedings of 9th international database engineering & application symposium (IDEAS 2005), Montreal, Canada, July 2005. IEEE, pp 187–199Google Scholar
  9. Berners-Lee T (1998) Relational databases on the semantic Web. Accessed 26 Dec 2014.
  10. Biblioteca Nacional De Espana (2012) Linked data at Spanish National Library. Accessed 26 Dec 2014
  11. Bizer C, Seaborne A (2004) D2RQ—Treating non-RDF databases as virtual RDF graphs. Poster presented at the 3rd international semantic web conference (ISWC 2004), Hiroshima, JapanGoogle Scholar
  12. Bizer C, Cyganiak R (2006) D2R Server—Publishing relational databases on the semantic web. Poster presented at the 5th international semantic web conference (ISWC 2006), Athens, Georgia, USAGoogle Scholar
  13. Blakeley C (2007) Virtuoso RDF views getting started guide. Accessed 26 Dec 2014
  14. British Library (2012) Linked data at the British Library. Accessed 26 Dec 2014
  15. Buccella A, Penabad MR, Rodriguez FR et al (2004) From relational databases to OWL ontologies. In: Proceedings of 6th Russian conference on digital libraries (RCDL 2004), Pushchino, RussiaGoogle Scholar
  16. Byrne K (2008) Having triplets—holding cultural data as RDF. In: Larson M, Fernie K, Oomen J et al (eds) Proceedings of the ECDL 2008 workshop on information access to cultural heritage. Aarhus, DenmarkGoogle Scholar
  17. Chebotko A, Lu S, Fotouhi F (2009) Semantics preserving SPARQL-to-SQL translation. Data & Knowledge Eng 68(10):973–1000CrossRefGoogle Scholar
  18. Curé O, Squelbut R (2005) A database trigger strategy to maintain knowledge bases developed via data migration. In: Bento C, Cardoso A, Dias G (eds) Progress in artificial intelligence: 12th Portuguese conference on artificial intelligence (EPIA 2005), Covilha, Portugal, December 2005. Lecture notes in computer science, vol 3808. Springer, Heidelberg, pp 206–217Google Scholar
  19. Cyganiak R (2005) A relational algebra for SPARQL. Hewlett Packard. Accessed 26 Dec 2014
  20. Das S, Srinivasan J (2009) Database technologies for RDF. In: Tessaris S, Franconi E, Eiter T et al (eds.) Reasoning web. Semantic technologies for information systems: 5th international summer school 2009. Lecture notes in computer science, vol 5689. Springer, Heidelberg, pp 205–221Google Scholar
  21. Deutsche National Bibliothek (2012) The linked data service of the German National Library. Accessed 26 Dec 2014
  22. Dragut E, Lawrence R (2004) Composing mappings between schemas using a reference ontology. In: Meersman R, Tari Z (eds) On the move to meaningful internet systems 2004: CoopIS, DOA, and ODBASE. Lecture notes in computer science, vol 3290. Springer, Heidelberg, pp 783–800Google Scholar
  23. Eisenberg V, Kanza Y (2012) D2RQ/Update: updating relational data via virtual RDF. In: Proceedings of the 21st international conference companion on World Wide Web (WWW’12 Companion), Lyon, France, April 2012. ACM, New York, pp 497–498Google Scholar
  24. Elliott B, Cheng E, Thomas-Ogbuji C et al (2009) A complete translation from SPARQL into efficient SQL. In: Desai BC (ed) Proceedings of the thirteenth international database engineering & applications symposium (IDEAS’09), Calabria, Italy, September 2009. CM, New York, USA, pp 31–42Google Scholar
  25. Elmasri R, Navathe SB (2010) Fundamentals of database systems. The Benjamin/Cummings, San FranciscoGoogle Scholar
  26. Garrote A, Moreno García MN (2011) RESTful writable APIs for the web of linked data using relational storage solutions. In: Bizer C, Heath T, Berners-Lee T et al (eds) Proceedings of the 4th linked data on the web wWorkshop (LDOW 2011), Hyderabad, India. CEUR Workshop Proceedings, vol 813Google Scholar
  27. Geller J, Chun SA, An YJ (2008) Toward the semantic deep web. Computer 41(9):95–97CrossRefGoogle Scholar
  28. Ghawi R, Cullot N (2007) Database-to-ontology mapping generation for semantic interoperability. Paper presented at the 3rd international workshop on database interoperability (InterDB 2007), held in conjunction with VLDB 2007, ViennaGoogle Scholar
  29. Gómez-Pérez A, Corcho-Garcia O, Fernandez-Lopez M (2003) Ontological engineering. Springer-Verlag, New YorkGoogle Scholar
  30. Heath T, Bizer C (2011) Linked data: evolving the web into a global data space. Morgan & Claypool, San RafaelGoogle Scholar
  31. Hellmann S, Unbehauen J, Zaveri A et al (2011) Report on knowledge extraction from structured sources. LOD2 Project. Accessed 26 Dec 2014
  32. Hendler J (2008) Web 3.0: chicken farms on the semantic web. IEEE Computer 41(1):106–108CrossRefGoogle Scholar
  33. Hert M, Ghezzi G, Würsch M et al (2011) How to “Make a Bridge to the New Town” using ontoaccess. In: Aroyo L, Welty C, Alani H et al (eds) The semantic web—ISWC 2011, Proceedings of the 10th international semantic web conference, part II, Bonn, Germany, October 2011. Lecture notes in computer science, vol 7032. Springer, Heidelberg, pp 112–127Google Scholar
  34. Knoth P, Robotka V, Zdrahal Z (2011) Connecting repositories in the open access domain using text mining and semantic data. In: Gradmann S, Borri F, Meghini C et al (eds) Research and advanced technology for digital libraries, Proceedings of the international conference on theory and practice of digital libraries 2011 (TPDL 2011), Berlin, Germany, September 2011. Lecture notes in computer science, vol 6966. Springer, Heidelberg, pp 483–487Google Scholar
  35. Konstantinou N, Spanos DE, Mitrou N (2008) Ontology and database mapping: a survey of current implementations and future directions. J Web Eng 7(1):1–24Google Scholar
  36. Konstantinou N, Spanos DE, Stavrou P et al (2010) Technically approaching the semantic web bottleneck. Int J Web Eng Technol 6(1):83–111CrossRefGoogle Scholar
  37. Konstantinou N, Houssos N, Manta A (2013) Exposing bibliographic information as linked open data using standards-based mappings: methodology and results. 3rd international conference on integrated information (IC-ININFO ’13), Elsevier, Prague, Czech RepublicGoogle Scholar
  38. Konstantinou N, Spanos DE, Mitrou N (2013) Transient and persistent RDF views over relational databases in the context of digital repositories. In: Garoufallou E, Greenberg J (eds) Metadata and semantics research. Proceedings of the 7th MTSR conference, Thessaloniki, Greece, November 2013. Communications in Computer and Information Science, vol 390. Springer, Heidelberg, pp 342–354Google Scholar
  39. Konstantinou N, Spanos DE, Houssos N et al (2014a) Exposing scholarly information as linked open data: RDFizing DSpace contents. Electronic Library 32(6):834–851CrossRefGoogle Scholar
  40. Konstantinou N, Kouis D, Mitrou N (2014b) Incremental export of relational database contents into RDF graphs. In: Akerkar R, Bassiliades N, Davies J et al (eds) Proceedings of the 4th international conference on web intelligence, mining and semantics (WIMS ’14), June 2014, Thessaloniki, Greece. ACM, New YorkGoogle Scholar
  41. Lu J, Cao F, Ma L et al (2007) An effective SPARQL support over relational databases. In: Christophides V, Collard M, Gutierrez C (eds) Semantic web, ontologies and databases: VLDB workshop (SWDB-ODBIS 2007), Vienna, Austria, September 2007. Lecture notes in computer science, vol 5005. Springer, Heidelberg, pp 57–76Google Scholar
  42. Mulwad V, Finin T, Syed Z et al (2010) Using linked data to interpret tables. In: Hartig O, Harth A, Sequeda J (eds) Proceedings of the first international workshop on consuming linked data (COLD 2010), Shanghai, China, November 2010. CEUR workshop proceedings. vol 667Google Scholar
  43. Poggi A, Lembo D, Calvanese D et al (2008) Linking data to ontologies. J Data Semantics 10:133–173Google Scholar
  44. Priyatna F, Corcho O, Sequeda J (2014) Formalisation and experiences of R2RML-based SPARQL to SQL query translation using morph. In: Proceedings of the 23rd international conference on World Wide Web (WWW’14), Seoul, Republic of Korea. ACM, New York, USA, pp 479–490Google Scholar
  45. Ramanujam S, Khadilkar V, Khan L et al (2010) Update-enabled triplification of relational data into virtual RDF stores. Int J Semantic Comput 4(4):423–451CrossRefGoogle Scholar
  46. Rodriguez-Muro M, Kontchakov R, Zakharyaschev M (2013) Ontology-based data access: ontop of databases. In: Alani H, Kagal L, Fokoue A et al (eds) The semantic web—ISWC 2013, Proceedings of the 12th international semantic web conference, October 2013, Sydney, Australia. Lecture notes in computer science, vol 8218. Springer, Heidelberg, pp 558–573Google Scholar
  47. Sahoo S, Halb W, Hellmann S et al (2009) A survey of current approaches for mapping of relational databases to RDF. World wide web consortium. Accessed 26 Dec 2014
  48. Sequeda JF, Tirmizi SH, Corcho O et al (2009) Direct mapping SQL databases to the semantic web: a survey. University of Texas, Austin, Department of Computer Sciences. Accessed 26 Dec 2014
  49. Sequeda JF, Miranker DP (2013) Ultrawrap: SPARQL execution on relational data. J Web Semantics 22:19–39CrossRefGoogle Scholar
  50. Sheth AP, Larson JA (1990) Federated database systems for managing distributed, heterogeneous, and autonomous databases. ACM Computing Surveys 22(3):183–236CrossRefGoogle Scholar
  51. Spanos DE, Stavrou P, Mitrou N (2012) Bringing relational databases into the semantic web: a survey. Semantic Web J 3(2):169–209Google Scholar
  52. Stevenson A (2011) Linked data—the future for open repositories? Presentation at the open repositories (OR 2011) conference, Austin, TXGoogle Scholar
  53. Tirmizi SH, Sequeda JF, Miranker DP (2008) Translating SQL applications to the semantic web. In: Bhowmick SS, Küng J, Wagner R (eds) Database and expert systems applications: 19th international conference (DEXA 2008), Turin, Italy, September 2008. Lecture notes in computer science, vol 5181. Springer, Heidelberg, pp 450–464Google Scholar
  54. Volz J, Bizer C, Gaedke M et al (2009) Discovering and maintaining links on the web of data. In: Bernstein A, Karger DR, Heath T et al (eds.) The semantic web—ISWC 2009: Proceedings of the 8th international semantic web conference, Washington DC, October 2009. Lecture notes in computer science, vol 5823. Springer, Heidelberg, pp 650–665Google Scholar
  55. Volz R, Handschuh S, Staab S et al (2004) Unveiling the hidden bride: deep annotation for mapping and migrating legacy data to the semantic web. J Web Semantics 1(2):187–206CrossRefGoogle Scholar
  56. Wache H, Vögele T, Visser U et al (2001) Ontology-based integration of information—a survey of existing approaches. In: Gómez-Pérez A, Gruninger M, Stuckenschmidt H et al (eds) Proceedings of the IJCAI-01 workshop on ontologies and information sharing, Seattle, USA, August 2001. CEUR Workshop Proceedings,, vol 47, pp 108–117Google Scholar
  57. Zhao S, Chang E (2007) From database to semantic web ontology: an overview. In: Meersman R, Tari Z, Herrero P (eds) On the move to meaningful internet systems: OTM 2007 Workshops. Lecture notes in computer science, vol 4806. Springer, Heidelberg, pp 1205–1214Google Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Nikolaos Konstantinou
    • 1
  • Dimitrios-Emmanuel Spanos
    • 1
  1. 1.National Technical University of AthensAthensGreece

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