Gems of PODS
Speaker: Wim Martens (University of Bayreuth)
Title: Querying Graph Data: Where We Are and Where To Go
Accompanying paper (pdf)
Slides (pdf)
Abstract: Although graph query languages such as Cypher, SQL/PGQ, and GQL take inspiration from theoretical languages such as conjunctive regular path queries (CRPQs), their pattern matching facilities have powerful extensions in order to cope with real world use cases. Four such extensions are (1) treatment of both nodes and edges, (2) variables that bind to paths or lists, (3) path modes, and (4) data filters.
The real-world design of these features has some issues, however, that renders some natural queries inexpressible and prevents query optimization opportunities. Furthermore, they make the language difficult to study. By necessity, these issues are inherited by recent formalizations that aimed at accurately describing the standards.
We present a variant of CRPQs with the extensions (1-4), aimed to provide researchers a clean model to study, and to provide language designers inspiration for how the standards can be tweaked to overcome the aforementioned issues. In the talk (and the accompanying paper), we discuss where the design of SQL/PGQ and GQL stands today and identify a host of opportunities in research and query language design.
Bio: Wim Martens is professor for Data Intensive Computing at the University of Bayreuth. He is interested in foundational aspects of data management (with a current focus on query language design), the Web, logic, complexity, and formal language theory. One of his goals is to find a good balance for making programming with data easy, intuitive, precise, and efficient. His work received several awards at SIGMOD and ICDT, and he was an invited speaker at STOC and PODS.
