I'm in the process of developing a .NET application that needs to be able to run without a database engine installed on the target machine.
It's predecessor used an mdb file to achieve this. Is there a better alternative now? The database will only have one user in 90% of cases. In the other 10% an standard SQL Server would be used.
The new version of SQL CE looks promising, as blogged by Scott Gu.
There is an ADO.NET Data Provider for SqLite. It provides a fully-functional, single assembly "database engine" that can be deployed with your application, and used without being "installed" on the target machine.
Is this going to run only on Windows boxes? If so, you have a database engine installed on every machine that is Windows 2000 or later, and that's Jet 4.0 (including DAO 3.6). So, as long as your deployment is limited to Windows and you're not compiling for 64-bit, you can continue using an MDB.