Db4o is an already established OODBMS solution for Java and .NET, providing a powerful and easy-to-use solution for object persistence. This library makes db4o accessible to Eiffel for .NET programmers, the source code is available here.
To learn how to start using db4o databases within Eiffel applications, you could first read the step-by-step guide for getting started.
Next, you could read this complete db4o_for_eiffel_manual.pdf User's and Developer's Manual] for a deeper understanding of how Eiffel is integrated in the .NET Framework, how to use the three querying mechanisms (Query-By-Example, SODA Query API and Native Queries) to query for Eiffel objects, and how to configure db4o databases for Eiffel classes, etc. The manual also discusses the issues and workarounds. It’s worth reading.
While reading the manual, you could try out this advanced example project.
We hope you could benefit from the project.