Real World Experience of db4o and/or Eloquera Database

Question

I am evaluating two object databases, db4o (http://www.db4o.com) and Eloquera Database (http://eloquera.com) for a coming project. I have to choose one. My basic requirement is scalability, multi user support and easy type evolution for RAD.

1. Please share your real world experience.

2. If you have both, can you compare these two? Which do you prefer?

Answer 1

For the last 2 years I've been using DB4O, and I'm now switching to Eloquera. My reasons, in order:

1. I'm building a commercial product, and the royalty based licensing on DB4O is WAY to high; DB4O said we could "talk about it", but I'm a very small development shop and giving away a huge chunk of each sale I make just doesn't make any sense when there's a perfectly good alternative.

2. I'm using the Db4oTool.exe to modify my assmeblies in a post-build step, and it really slows down the build process. Eloquera doesn't need to modify my assemblies.

3. I found a bug in the DB4O code, and it took many many months before it was integrated into their codebase. I have found bugs in Eloquera and they fixed them in a day or two

4. DB4O is not yet on .NET 4 (although they finally have an early beta). DB4O is the ONLY thing holding me back from using VS2010 (and .NET 4). I tried migrating to VS2010 but VS2010 automatically converts all unit tests to .NET 4, so all of my persistence related unit tests immediately failed.

5. DB4O is not really designed to be thread-safe.

6. DB4O has features and many API features that are obviously ported from Java.

Robert