SRP Temporary Research Position on graph data management

The Centre Inria de l’Université de Grenoble groups together almost 600 people in 22 research teams and 8 research support departments.

Staff is present on three campuses in Grenoble, in close collaboration with other research and higher education institutions (Université Grenoble Alpes, CNRS, CEA, INRAE, …), but also with key economic players in the area.

The Centre Inria de l’Université Grenoble Alpes is active in the fields of high-performance computing, verification and embedded systems, modeling of the environment at multiple levels, and data science and artificial intelligence. The center is a top-level scientific institute with an extensive network of international collaborations in Europe and the rest of the world.

Within the framework of the GraphRec Project (http://tyrex.inria.fr/graphrec), the Tyrex team investigates efficient graph exploration techniques with an algebraic approach, and recently an extended relational algebra for optimising recursive queries [1,4]. This is achieved through the introduction of a new fixpoint operator, new rewrite rules, and new query evaluation plan enumeration techniques that enable new query evaluation plans that used to be out of reach with earlier approaches. One important application of this theory is the optimization of recursive queries over graphs, such as the ones found in recent graph query languages [2,3]. In particular, the theory muRA has been proved very useful to optimize UCRPQs queries over knowledge graphs.
Property graphs are even more general than knowledge graphs as they allow both edges and vertices to be annotated not only with a label but also with a list of key/value pairs. This led to the development of specific query languages for property graphs with various characteristics [3]. The proposed research includes further investigating extensions of this theory in the context of query languages suited for more general graphs such as property graphs, in particular in the presence of schema information.



References:

[1] Louis Jachiet, Pierre Genevès, Nils Gesbert, Nabil Layaïda: On the Optimization of Recursive Relational Queries: Application to Graph Queries. SIGMOD Conference 2020, pages 681-697. https://hal.inria.fr/hal-01673025/document

[2] Angela Bonifati, George H. L. Fletcher, Hannes Voigt, Nikolay Yakovets:
Querying Graphs. Synthesis Lectures on Data Management, Morgan & Claypool Publishers 2018

[3] Chandan Sharma, Roopak Sinha, Kenneth Johnson: Practical and comprehensive formalisms for modelling contemporary graph query languages. Inf. Syst. 102: 101816 (2021).

[4] Amela Fejza, Pierre Genevès and Nabil Layaïda: Efficient Enumeration of Recursive Plans in Transformation-based Query Optimizers. In Proceedings of the 50th International Conference on Very Large Databases (VLDB'24), 2024 (to appear), 2024.

The candidate will be respondible for conducting research activities at the highest level in data management.

As a first step, works will consist in the further development and publication of the approach co-investigated in [5].

References:

[5] Chandan Sharma, Pierre Genevès, Nils Gesbert, Nabil Layaïda: Schema-Based Query Optimisation for Graph Databases. arXiv:2403.01863 preprint, 2024.  https://arxiv.org/abs/2403.01863

• Subsidized meals
• Partial reimbursement of public transport costs
• Leave: 7 weeks of annual leave + 10 extra days off due to RTT (statutory reduction in working hours) + possibility of exceptional leave (sick children, moving home, etc.)
• Possibility of teleworking (90 days / year) and flexible organization of working hours (except for internship)
• Social, cultural and sports events and activities
• Access to vocational training
• Social security coverage under conditions

Gross salary per month from 3 085 € (depending on international experience and qualifications).