EACH OF THE LINE BELOW WILL GIVE USEFULL INFORMATION ABOUT SQL SERVER COMPACT
****START MSDN LIBRARY THEN IN THE SEARCH AREA PASTE ONE OF THE LINK BELOW****  

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1:Local Data Overview
2:SQL Server Compact 3.5 and Visual Studio
3:How to: Add a SQL Server Compact 3.5 Database to a Project
4:Walkthrough: Creating a SQL Server Compact 3.5 Database
5:How to: Deploy a SQL Server Compact 3.5 Database with an Application 
6:SQL Server Connection Pooling (ADO.NET)
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