Server Explorer and SQL Server Object Explorer refer to this.
The .mdf file in Server Explorer is specifically meant to serve your local project. In your case, this .mdf file should contain the schema you defined in the Dataset Designer, such as tables, columns, relationships, etc.
You need to access its content through Microsoft SQL Server Database File (SqlClient). It will not contain any actual data unless you manually add data or import data. This file is created to allow you to build and test data access logic within your local environment.
The .mdf file here differs significantly from the traditional .mdf file found in SQL Server, and I believe that the naming convention used by Visual Studio can be quite ambiguous. I suggest it might be better to consider it as a .vmdf file.
Best regards,
Mikey Qiao
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