.NET and Oracle data access

Question

I am trying to do something like this:

Public Sub (ByVal boolTest As Boolean)
Dim objConnecton As System.Data.Common.DbConnection
Try

  If boolTest Then
         objConnecton = New SqlConnection
  Else
          objConnecton = New OracleConnection 
  End If
  Catch ex As Exception

Finally
  'Cleanup here
End Try

This works with version 2.112.1.0, of Oracle.DataAccess, but does not with version 10.2.0.100. With version 10.2.0.100, I get the following compilation error:

"Value of type 'Oracle.DataAccess.Client.OracleConnection' cannot be converted to 'System.Data.Common.DbConnection'"

I am trying to initialise the connection object with an instance of either SQLConnection or OracleConnection depending on the value of the Boolean.

Why do I get this error?

Answer 1

Why do I get this error?

The later (10.2+) versions of the Oracle clients for .NET do not derive from the standard .NET framework classes, such as DbConnection. This has the unfortunate side effect of requiring a fair bit more work if you want to support multiple databases seamlessly, as you can no longer just use the base classes in System.Data.Common.