Architecture of a Database System (2007) [pdf]
If you are interested in the life of a query but in a modern distributed database, this blog post from my colleague at Fauna illustrates the data flow of a global transactional database <a href="https://blog.fauna.com/the-life-of-a-faunadb-query" rel="nofollow">https://blog.fauna.com/the-life-of-a-faunadb-query</a>