推荐序一 We released ClickHouse in open-source in 2016, four years ago. And as far as I know, this book is going to be the first published book on ClickHouse. Why do I appreciate that so much? When we released ClickHouse, we had only one goal in mind, to give people the fastest analytical DBMS in the world. But now, after a few years, I see many more opportunities. We can make ClickHouse an example of the most community and developers friendly open-source product. According to Eric S. Raymond, there are two models of software development：the “Cathedral” and the “Bazaar” model. In the first model, the software is developed by a closed team of a few developers who “do the right thing”. An example of the “Cathedral” model is SQLite that is developed mostly by a single person—Richard Hipp. In con…