Web-Scale Data Management

This course addresses the challenges of Data Management at Web-scale. Especially, it covers the need for large-scale distributed data storage systems. The lecture therefore introduces step-by-step increasingly complex distributed storage systems, leading up to modern implementations of different NoSQL data storage systems. The challenges arising from such systems are presented and discussed, especially focusing on the CAP theorem and the resulting trade-offs with respect to data models, transactional power, query expressivity, and replication consistency. These discussions lead to different variants of NoSQL database systems, like Key-Value Stores, Document Stores, Wide-Columnar stores, and Graph Databases. The advantages, disadvantages, and general properties of these systems are discussed in more detail. The course focuses also on database transactions, and the implications those have in modern, Web-scale application development and deployment, i.e., there is special focus on distributed transactions and consistency guarantees of different data management systems and methods.