Lecture
This lecture covers the concept of views in SQL, which simplify the query writing process by allowing the definition of conceptual tables derived from existing tables. Topics include view creation, materialized views, tradeoffs, maintenance, and optimizations for cube building. The instructor explains the advantages of materialized views, issues in view materialization, incremental maintenance, and different view maintenance policies. Additionally, the lecture delves into computing data cubes from existing views, choosing which views to build, and cube building optimizations such as smallest-parent, cache-results, and share-sorts. The session concludes with an overview of OLAP, top-k queries, and optimizations for top-k queries.