In Visual Studio LightSwitch, when you design your data model through the Data Designer you are either creating new tables or attaching to external data sources. When you create new tables, LightSwitch automatically creates them in the internal database, also known as the Intrinsic database or ApplicationData. In the first version of LightSwitch in Visual Studio 2010 we used SQL 2008 Express for the internal database development. Now with LightSwitch in Visual Studio 11 we are using SQL Server LocalDB. (Note: LocalDB is only used during development time. When you deploy your app you can choose to deploy to any version of SQL Server.)

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