ADO.NET is a set of libraries included in the .NET framework to facilitate the communication of applications with various data storage mechanisms. These libraries form the basis for all third parties to provide data access services to users of .NET applications. ADO.NET is a mature set of API's that have been largely unchanged since .NET 2.0.  VistaDB supports ADO.NET from 2.0 through the latest version of .NET.  There are some extensions added in .NET 4 - notably PLINQ - that are not supported at this time.

The ADO.NET Object Model

ADO.NET at its most basic level was designed to help developers work efficiently with multi tier databases, across intranet or Internet scenarios. This is a tall order for a single framework, but I think they managed to pull it off quite well.

It's helpful to view the object model as being split into two parts - A connected and a disconnected side of the model. Even though there is no distinction between the two "sides", it helps me to visualize how the data object was intended to be used.

See the specific topics below for more information:

Connected ADO.NET Objects

Disconnected ADO.NET Objects

ADO.NET Entity Framework

ADO.NET 3.5 SP1 added a new higher-level data access strategy called Entity Framework.  VistaDB supports Entity Framework 4.0 at later through a separate provider assembly that works with the VistaDB engine.  Depending on the version of Entity Framework that you are employing in your application you'll need to pick the appropriate configuration and provider assembly.  For more information see Using VistaDB with Entity Framework - Registering the Provider.