Designing Data-Intensive Applications, 2nd Edition

Chapter 4. Storage and Retrieval

One of the miseries of life is that everybody names things a little bit wrong. And so it makes everything a little harder to understand in the world than it would be if it were named differently. A computer does not primarily compute in the sense of doing arithmetic. […] They primarily are filing systems.

Richard Feynman, Idiosyncratic Thinking seminar (1985)

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This will be the 4th chapter of the final book. The GitHub repo for this book is https://github.com/ept/ddia2-feedback.

If you’d like to be actively involved in reviewing and commenting on this draft, please reach out on GitHub.

On the most fundamental level, a database needs to do two things: when you give it some data, it should store the data, and when you ask it again later, it should give the data back to you.

In Chapter 3 we discussed data models and query languages—i.e., the format in which you give the database your data, and the interface through which you can ask for it again later. In this chapter we discuss the same from the database’s point of view: how the database can store the data that you give it, and how it can find the data again when you ask for it.

Why should you, as an application developer, care how the database handles ...