I study data intensive systems. I am particularly interested in
query language design and engineering,
foundations of databases,
and data analytics.
I am currently investigating
challenges in the management of massive graphs such as social networks, linked open data, and biological networks.
You can find information about students and post-docs I've collaborated with on my teaching & mentoring page.
If you are a student interested in a thesis topic in data intensive systems, please feel free to get in touch.
- Landmark indexing for evaluation of label-constrained reachability queries.
Lucien Valstar, George Fletcher, Yuichi Yoshida. SIGMOD 2017. open source code.
- gMark: schema-driven generation of graphs and queries.
Guillaume Bagan, Angela Bonifati, Radu Ciucanu, George Fletcher, Aurélien Lemay, Nicky Advokaat. IEEE Transactions on Knowledge and Data Engineering, 2017.
See also our demo at
VLDB 2016 and open source code.
- Structural characterizations of the navigational expressiveness of relation algebras on a tree. George Fletcher, Marc Gyssens, Jan Paredaens, Dirk Van Gucht, and Yuqing Wu. J. Comput. Syst. Sci., 2016.
- Relative expressive power of navigational querying on graphs.
George Fletcher, Marc Gyssens, Dirk Leinders, Dimitri Surinx, Jan Van den Bussche, Dirk Van Gucht, Stijn Vansummeren, Yuqing Wu. Information Sciences, 2015.
- Similarity and
bisimilarity notions appropriate for characterizing indistinguishability in fragments of the calculus of relations.
George Fletcher, Marc Gyssens, Dirk Leinders, Jan Van den Bussche, Dirk Van Gucht, Stijn Vansummeren. J. Log. Comput., 2015.
- Efficient and scalable trie-based algorithms for computing set containment relations.
Yongming Luo, George Fletcher, Jan Hidders, Paul De Bra. ICDE 2015, Seoul.
- Principles of guarded structural indexing.
Francois Picalausa, George Fletcher, Jan Hidders, Stijn Vansummeren. ICDT 2014, Athens, Greece.
- On reflection in linked data management.
George Fletcher. DESWeb 2014, Chicago (slides).
- External memory k-bisimulation reduction of big graphs.
Yongming Luo, George Fletcher, Jan Hidders, Yuqing Wu, Paul De Bra. CIKM 2013, San Francisco.
- A structural approach to indexing triples.
Francois Picalausa, Yongming Luo, George Fletcher, Jan Hidders, Stijn Vansummeren. ESWC 2012, Heraklion.
- Efficient external-memory bisimulation on DAGs.
Jelle Hellings, George Fletcher, Herman Haverkort. SIGMOD 2012, Scottsdale (open source code).
- Towards a theory of search queries.
George Fletcher, Jan Van den Bussche, Dirk Van Gucht, and Stijn Vansummeren.
ACM Transactions on Database Systems, 2010.
- Towards a general framework for effective solutions to the data mapping problem.
George Fletcher and Catherine Wyss. Journal on Data Semantics, 2009.
- Thinking about computational thinking.
James J. Lu and George Fletcher. SIGCSE 2009, Chattanooga.
Edited version also appeared in Communications of the ACM, 2009.
- A methodology for coupling fragments of XPath with structural indexes for XML documents.
George Fletcher, Dirk Van Gucht, Yuqing Wu, Marc Gyssens, Sofía Brenes, and Jan Paredaens.
Information Systems, 2009.
For more details, you can also check out my entries at