Native Support for Processing Interval Timestamped Data in RDBMSs

by Johann Gamper, Free University of Bozen-Bolzano

May 20th 2015 @ 14:30, in Room Ofek

In this invited talk Johann Gamper will present his work about

Native Support for Processing Interval Timestamped Data in RDBMSs

Abstract:

Time is ubiquitous, and it is hard to think of an application that has not to deal with temporal information in one form or another. Despite this fact, the support for managing and querying temporal data in relational databases is limited.

In this work we propose a relational algebra solution that provides native support for querying temporal relations, where each tuple has associated a time interval that represents the time the tuple is valid in the modelled reality. We define the temporal algebra by reducing the temporal operators to the corresponding non-temporal operators with the help of two primitives, namely a temporal splitter and temporal aligner. Our algebra supports three important properties for temporal data: snapshot reducibility, extended snapshot reducibility, and change preservation.

We have implemented the temporal primitives and reduction rules in the kernel of PostgreSQL to get native database support for processing interval timestamped data. The support is comprehensive and includes outer joins, antijoins, and aggregations with predicates and functions over the time intervals of argument relations. The implementation and empirical evaluation confirm effectiveness and scalability of our solution that leverages existing database query optimization techniques.

Speaker:

Johann Gamper is an associate professor at the Faculty of Computer

Science of the Free University of Bozen-Bolzano. He received a M.Sc. degree in Computer Science from the TU Vienna (1989) and a Ph.D. degree in Computer Science from the RWTH Aachen (1996). His main research interests include data intensive systems with a particular focus on advanced database technologies for processing time and space referenced data, data warehousing, data analysis, and approximate query answering. He is author of 80+ publications in peer-reviewed international journals and conference proceedings.

Contact Info: Matteo Lissandrini (ml@disi.unitn.eu)