OReilly - Understanding MySQL Internals

This book can be useful for a number of readers: a developer trying to extend MySQL in some way; a DBA or database application programmer interested in how exactly MySQL runs his queries; a computer science student learning about database kernel development; a developer looking for ideas while working on a product that requires extensive database functionality that he must implement himself; a closed-source database developer wondering how in the world MySQL runs its queries so fast; a random, curious computer geek who has used MySQL some and wonders what is inside; and, of course, anybody who wants to look smart by having a book on MySQL internals displayed on his shelf.

Although MySQL source is open in the sense of being publicly available, it is in essence closed to you if you do not understand it. It may be intimidating to look at several hundred thousand lines of code written by gifted programmers that elegantly and efficiently solves difficult problems one line at a time. To understand the code, you will need a measure of the inspiration and perspiration of those who created it. Hopefully, this book can provide enough guidance to remove those barriers and to open the source of MySQL for you.

I do not believe it is possible to understand and appreciate MySQL strictly through a conceptual discussion. On a high conceptual level MySQL is very simple. It does not implement many revolutionary ideas. It sticks to the basics. Why is it so popular then? Why do we know enough about it for O’Reilly to be willing to publish a book on its internals?