The compile is basically saying it does not know what those objects are because it does not know where to find their definitions.
You need to either fully qualify each object with its full namespace path (eg System.Data.SqlClient.SqlConnection) so the compile knows where to locate those objects, or you can add a "using" statement if your coding in C# (or Import for VB
) to your code to tell the compiler what namespaces are available in your code.
C#: using System.Data.SqlClient;
: Import System.Data.SqlClient