Software Design by Example in Python 18: A Database

The book is an excellent guide for anyone going from "just programming" to building larger projects. It's like a choose-your-own adventure, but the adventure is learning to build very complex software as a composition of much simpler patterns.
- Jennifer Moore

One of the joys of writing is learning new things yourself in order to explain them to others. By that standard Chapter 18: A Database was more joyful than most, though it didn’t feel that way at the time. I knew at the outset that a relational database using B-trees wouldn’t fit in my one-hour limit, so I started reading about log-structured databases. Once my head stopped swimming I tried to build one, and quickly realized that if I wanted it to be manageable I would have to ignore the same issues around atomic multi-file operations that I ignored in the chapter on a file archiver. I thought I would come back to them, but time, interest, and space all ran out; if there’s ever a sequel to this book, I hope that will be its first chapter.

Terms defined: block (of memory), compact (data or files), garbage collection, key-value store, log-structured database, null byte, page.