Hi ,
I'm comparing various opensource database to embedded in my new .Net Windows Client application and would like to get some recommendation. Aside from those general stuff , the DB simply needs to:

1. Secure from the User access. ie. User has no direct way to manipulate the data in the database file and the file can be encrypted

2. Allow multi-connections. Actually there will be only 1 user running the application, but multi threads will be access the db.

3. Can scale multi GB of data. Although this is unlikely, it still could be a possibility depends on user's usage.

I was looking into SQL Express (not opensource but free) but it has admin tools that allow user to have direct access to the db data and only allow 1GB data.

Now, I am comparing MySQL and Firebird. Could anyone recommend any other and provide some Pro/Con information?

Many thanks.

SQL Express 2005 does not HAVE to let the user have access to the data. It can be configured to prevent that access from all but the most astute geeks.

-PatP