The SQL Server Compact 3.5 SP2 Desktop runtime (x86 and x64) is installed with SQL Server 2008 R2 and Visual Studio 2010.
Microsoft SQL Server Compact 3.5 Service Pack 2 for Windows Desktop
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=e497988a-c93a-404c-b161-3a0b323dce24
Microsoft SQL Server Compact 3.5 Service Pack 2 for Windows Mobile
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=5544c638-c532-48e3-871c-58b49c5d855c
Microsoft SQL Server Compact 3.5 Service Pack 2 Server Tools
http://www.microsoft.com/downloads/details.aspx?familyid=5DEEC9D5-C216-446E-A003-5D6026AD19B3&displaylang=en
Microsoft SQL Server Compact 3.5 Service Pack 2 Books Online
http://www.microsoft.com/downloads/details.aspx?FamilyID=746c3a6e-ffb1-4c92-93fa-b3ba41fde681&displaylang=en
SQL Server Compact 3.5 SP2 includes a host of new features including the following:
- Support for the Transact-SQL Editor in Visual Studio 2010 that can be used to run free-text T-SQL queries and to view query show-plans for optimizing queries.
- Exposes the Change Tracking feature as an application programming interface (API), namely, System.Data.SqlServerCe.SqlCeChangeTracking. The new Change Tracking API provides the ability to configure, enable, and disable change tracking on a table, and to access the change tracking data for the table.
- New assembly versioning support and directory structure that enables the SQL Server Compact applications that use private deployment to load SQL Server Compact assemblies from within the application folder if they are of a higher version than that in the global assembly cache (GAC).
- Support added for deploying the 64-bit version of SQL Server Compact using the ClickOnce deployment.
Additional information about new features and bugs fixed in SP2 here: http://blogs.msdn.com/sqlservercompact/archive/2010/04/14/microsoft-sql-server-compact-3-5-with-service-pack-2-released-with-visual-studio-2010-and-on-the-web.aspx
and here: http://erikej.blogspot.com/2009/10/whats-new-in-sql-server-compact-35-sp2.html
A list of post SP2 fixes is avilable here: http://erikej.blogspot.com/2010/08/sql-server-compact-35-sp2-downloadable.html
Information about a private deployment issue with the Entity Framework DLL (and a solution) is described here:http://blogs.msdn.com/sqlservercompact/archive/2010/05/12/troubleshooting-problem-with-private-deployment-of-sql-server-compact-3-5sp2-entity-dll.aspx
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