Nullable Types and ADO.NET Parameters
Hello there null coalescing operator
As most people are aware the .NET 2.0 framework supports nullable value types. There are many articles on this topic and a few that address the issues of using nullable types in combination with your ado.net code. However, most of these discuss the issue of using nullable types in combination with the DbDataReader objects, though few address the conflicts that arise when using a nullable type to set or get an ado.net parameter value.