Simplest database implementation [closed]

Question

I am looking for a really simple database implementation; basically one with no complex parsing SQL engine. What I am looking for is something demonstrating B+ trees and ACID storage (Suitable for educational purposes). What I have found up-till now form my current searches was hamster-db. I am looking for something even simpler with a smaller code-base. If there is any such opensource project in your knowledge please let me know.

Answer 1

The University of Wisconsin Databases group uses their own small relational database, minirel, to teach the undergraduate databases class. I just took it, actually; it's enlightening. My semester's assignments are posted publicly. I'm sure the faculty would be willing to part with the source code used at each step.

In the undergraduate class, we do not implement B+ trees or ACID components, but it appears that the larger project does include them.