I highly recommend Rob's book. After fighting with SqlClient in the compact
framework for close to a week and finally discovering that, due to our SQL
Server installation, I would never be able to connect to it without changing
some settings on the server that cannot be touched without breaking some
existing apps, I went and purchased his book. In less then 2 hours, I had
installed, configured, and was finally able to watch my mobile app running
against live data from the server. I definitely get the impression that
Microsoft wants developers to use Sql Sever CE for all database developement
on the .NET Compact Framework since even their FAQ under data access only
discusses Sql Sever CE, and the documentation on System.Data.SqlClient on the
Compact Framework is next to nonexistant.