ADO.NET 3.5 Cookbook, 2nd Edition

Chapter 2. Working with Disconnected Data Objects

2.0. Introduction

ADO.NET has both connected and disconnected classes. Connected classes let you retrieve and update data in underlying data sources. They include the Connection, Command, DataReader, and DataAdapter classes. Each data provider is responsible for implementing the connected classes. Disconnected classes let you access and manipulate offline the data you retrieved using the connected classes and later synchronize it with the underlying data source using the connected classes. The disconnected classes include the DataSet, DataTable, DataColumn, DataRow, DataView, DataRelation, and Constraint classes. The disconnected classes are part of the ADO.NET classes in the .NET Framework. The recipes in this chapter discuss creating, working with, and managing the ADO.NET disconnected objects.

The DataSet is a disconnected, in-memory relational database that provides sophisticated navigational capabilities. It acts as a container for other objects, including DataTable, DataColumn, DataRow, and DataRelation. You can work with the data in these objects programmatically or you can data bind DataSet and DataTable objects to a variety of Windows Forms and Web Forms controls.

The DataSet and DataTable objects are data source-independent. Within these objects, .NET Framework data types are used to define column data types within tables. These data types are not the same as .NET provider native data types—provider data types are mapped to ...