NoSQL database systems are very popular in agile software development. Naturally, agile deployment goes hand-in-hand with database schema evolution. The main aim of this tutorial is to present to the audience the current state-of-the-art in continuous NoSQL schema evolution and data migration. We present case studies on schema evolution in NoSQL databases and survey existing approaches to schema management and schema inference, as implemented in popular NoSQL database products, and also as proposed in academic research. Further, we present approaches for extracting schema versions and analyze different methods for efficient NoSQL data migration. Finally, open research questions and further research opportunities are represented. (tutorial paper)
Uta Störl is a professor at Darmstadt University of Applied Sciences. Her research focuses on database technologies for Big Data and Data Science. Before, she worked for Dresdner Bank.
Meike Klettke is a professor for Data Science at the University of Rostock. She works on database evolution and reverse engineering of databases.
Stefanie Scherzinger is a professor at the University of Passau. Her research is influenced by her experience as a software engineer at IBM and Google.
We present an empirical study on the schema imposed on NoSQL databases by applications, as well as the dynamics of NoSQL schema evolution.
In this part we discuss different architectures and existing solutions for NoSQL schema management. Here, we present research approaches as well as first products.
We present solutions for NoSQL evolution management. Besides a language for declaring NoSQL schema evolution operations, we focus on approaches for extracting schema versions.
Based on the previous parts, we present different data migration strategies and discuss their quantitative assessment.
Finally, we outline open research problems as potential directions for further research.