English
A polynomial-time approximation algorithm for counting words accepted by an NFA. Invited talk at the the 53rd ACM Symposium on Theory of Computing (STOC 2021), Virtual Event, Rome, Italy, June 2021.
Querying in the age of graph databases and knowledge graphs, with Claudio Gutierrez and Juan F. Sequeda. Tutorial given at the SIGMOD International Conference on Management of Data (SIGMOD 2021), Virtual Event, Xi’an, Shaanxi, China, June 2021.
Data management in the COVID-19 pandemic: an opportunity, some barriers and a failure. 103rd Annual Conference of The Association for Education in Journalism and Mass Communication (AEJMC 2020), August 2020.
The Millennium Institute for Foundational Research on Data. CACM Latin America Virtual Workshop, April 2020.
Foundations of modern graph query languages. Ad Hoc on SQL Extensions Property Graphs, June 2017.
A note on computing certain answers to queries over incomplete databases. 11th Alberto Mendelzon International Workshop on Foundations of Data Management (AMW'17), Montevideo, Uruguay, June 2017.
Consistent Query Answering: a personal perspective. Invited talk at the Special Event in Honor of Leo Bertossi's Induction as First AMW Fellow, Montevideo, Uruguay, June 2017.
The Semantic Web: a lightweight data integration platform. Invited talk at the Information Communications Technologies \& High Performance Computing Workshop, Chile--Japan Academic Forum 2016, Puerto Natales, Chile, November 2016.
Foundations of Data Exchange and Metadata Management. Invited talk at the Ron Fagin Special Event, ACM SIGMOD/PODS Conference, San Francisco, CA, USA, June 2016.
Classical DB Questions on New Kinds of Data, with Pablo Barceló. Tutorial given at the Dagstuhl seminar Foundations of Data Management. Schloss Dagstuhl, Germany, April 2016.
Querying Semantic Web Data With SPARQL, with Jorge Perez. Tutorial given at the 1st School on Efficient Extraction of Semantic Web Data, Chile, January 2015.
Querying Semantic Web Data with SPARQL (and SPARQL 1.1). A talk given at Beihang University, China, November 2014.
Querying Semantic Web Data with SPARQL (and SPARQL 1.1). A talk given at Peking University, China, November 2014.
Expressive Languages for Querying the Semantic Web. Invited talk at Dagstuhl seminar Querying and Reasoning Under Expressive Constraints. Schloss Dagstuhl, Germany, August 2014.
Expressive Languages for Querying the Semantic Web. 33rd ACM SIGMOD-SIGACT-SIGART Symposium on Principles of Database Systems, (PODS'14), Snowbird, UT, USA, June 2014. (Note: A first version of this presentation was prepared by Andreas Pieris)
From the Web of Documents to the Web of Data. A talk given at the INDO-CHILE Workshop on Big Data, Goa, India, June 2014.
Discovering XSD Keys from XML Data. A talk given at Beihang University, China, August 2013.
Querying Semantic Web Data with SPARQL (and SPARQL 1.1). Invited tutorial at the 29th British National Conference on Databases (BNCOD'13), Oxford, UK, July 2013.
Discovering XSD Keys from XML Data. A talk given at the University of Oxford, UK, May 2013.
RDF and SPARQL: Two basic components of the Web of data. A talk given at the Universidad de Valladolid, Spain, April 2013.
Navigation in SPARQL 1.1. A talk given at the University of Oxford, UK, November 2012.
Data Exchange and Metadata Management. Invited talk at Dagstuhl seminar Foundations and Challenges of Change and Evolution in Ontologies. Schloss Dagstuhl, Germany, October 2012.
Paths in semantic search: A back and forth story. Invited talk at Dagstuhl seminar Semantic Data Management. Schloss Dagstuhl, Germany, April 2012.
Data Exchange beyond Complete Data. Invited talk at Dagstuhl seminar Foundations of distributed data management. Schloss Dagstuhl, Germany, October 2011.
Exchanging more than Complete Data. Invited talk at the 5th International Conference on Web Reasoning and Rule Systems (RR'11). Galway, Ireland, August 2011.
Exchanging more than Complete Data. Invited talk at the 24th International Workshop on Description Logics (DL'11), Barcelona, Spain, July 2011.
Querying Semantic Web Data with SPARQL: State of the Art and Research Perspectives. Invited tutorial at the 30th ACM SIGMOD-SIGACT-SIGART Symposium on Principles of Database Systems (PODS'11), Athens, Greece, June 2011.
Data Exchange in the Relational and RDF Worlds. Invited talk at the 3th International Workshop on Semantic Web Information Management (SWIM'11), Athens, Greece, June 2011.
Schema Mapping Management in Data Exchange Systems. Invited tutorial at the V Alberto Mendelzon International Workshop on Foundations of Data Management (AMW 2011), Santiago, Chile, May 2011.
Datalog as a Query Language for Data Exchange Systems. Datalog 2.0, Oxford, UK, March 2010.
Semantic Web: Query Languages for RDF and RDFS. Workshop on Emerging Topics in the Web, Santiago, Chile, November 2009.
Foundations of RDF Databases. Invited tutorial at Reasoning Web: Semantic technologies for information systems - 5th International Summer School, Brixen-Bressanone, Italy, August 2009.
SPARQL over RDF, and its possible extensions to RDFS. Invited talk at the Joint SWDB & ODBIS workshop on Semantic Web, Ontologies, Databases (SWDB-ODBIS 2007), Vienna, Austria, September 2007.
SPARQL - Where are we? Current state, theory and practice.Tutorial given at the 4th European Semantic Web Conference (ESWC 2007), Innsbruck, Austria, June 2007.
RDF and SPARQL: Two Basic Components of the Semantic Web. A talk given at The University of Edinburgh, Edinburgh, Scotland, UK, January 2007.
Locality of Queries and Transformations. 4th IFIP International Conference on Theoretical Computer Science, Santiago, Chile, August 2006.
XML Data Exchange. 2nd International Workshop on Exchange and Integration of Data, Brixen-Bressanone, Italy, June 2006.
Locally Consistent Transformations and Query Answering in Data Exchange. A talk given at The Isaac Newton Institute, University of Cambridge, UK, March 2006.
XML Data Exchange: Consistency and Query Answering. 24th ACM SIGMOD-SIGACT-SIGART Symposium on Principles of Database Systems, Baltimore, Maryland, USA, June 2005.
XML Data Exchange: Consistency and Query Answering. A talk given at The University of Edinburgh, Edinburgh, Scotland, UK, March 2005.
XML Data Exchange: Consistency and Query Answering. A talk given at Dagstuhl seminar Foundations of Semistructured Data, Wadern, Germany, February 2005.
Well-designed XML Data. A talk given at IBM Almaden Research Center, San Jose, California, USA, August 2004.
Well-designed XML Data. A talk given at IBM T.J. Watson Research Center, Hawthorne, New York, USA, June 2004.
Locally Consistent Transformations and Query Answering in Data Exchange. A talk given at The State University of New York, Buffalo, USA, April 2004.
An Information-Theoretic Approach to Normal Forms for Relational and XML Data. 22nd ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems (PODS'03), San Diego, USA, 2003.
What's Hard about XML Schema Constraints? 13th International Conference on Database and Expert Systems Applications (DEXA'02), Aix en Provence, France, 2002.
A Normal Form for XML Documents. 21st ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems (PODS'02), Madison, USA, 2002.
A Normal Form for XML Documents. A talk given at Carleton University, Ottawa, Canada, February 2002.