Earlier this year the book club of our company has studied excellent book: Martin Kleppmann - Designing Data-Intensive Applications This is the best book I have read about building complex scalable software systems. 💪 As usually I prepared an overview and mind-map. Chapter 2: What is data model. Different relations between the data. Relational, Document, Graph data models. Which one is better and when. Schema-on-write, schema-on-read (schemaless). Data locality.