Does anyone know of a tool similiar to RedGate's SQL Data Compare that works with Microsoft SQL Server Compact 3.5?
Have you tried SQL Compare from starinix? They say it supports SQL Server (All Editions) so that may include compact edition.
This software does work as I have used it (for Yukon). It's also freeware which saves worrying about licensing.
In the end I solved this problem by Exporting my 2 SQL Server Compact Databases to SQL Server Express 2005 (although 2008 would work) using Data Port Console.
I then compared them using Red Gate SQL Data Compare.
This solution works just fine for me.
Not sure, but you could also have a look at the Apex SQL tools - Apex SQL Diff and Apex SQL DataDiff. There website is here. They don't specifically mention SQL Server Compact - but I'm sure you could inquire with them.
Red-Gate and Apex are my #1 choices for any kind of SQL tools :-)
Marc