Related code example: http://msdn.microsoft.com/en-us/library/ff769953.aspx
Learn how to use Microsoft Visual Studio 2010 to create a Visual Web Part that uses a Microsoft Business Connectivity Services (BCS) external content type in Microsoft SharePoint Server 2010 to read and write data to the AdventureWorks sample database.
Maybe I'm missing something... why not just use a RequiredFieldValidator? (5:18)
jhayes615 6 months ago