Understanding ADO.NET Components

ADO.NET Components
The ADO.NET is designed to work with multiple kinds of data sources in same fashion. You can categorize ADO.NET components in three categories: disconnected, common or shared and the .NET data providers. The disconnected components build the basic ADO.NET architecture. You can use these components (or classes) with or without data providers. For example, you can use a DataTable object with or without providers and shared or common components are the base classes for data providers. Shared or common components are the base classes for data providers and shared by all data providers. The data provider components are specifically designed to work with different kinds of data sources. For example, ODBC data providers work with ODBC data sources and OleDb data providers work with OLE-DB data sources.
Figure represents the ADO.NET components model and how they work together:

A data provider is a set of components, such as Connection, Command, DataAdapter and DataReader. The Connection is the first component that talks to a data source. The Connection object establishes a connection to a data source and works as a connection reference in Command and DataAdapter objects. A Command object executes a SQL query and stored procedures to read, add, update, and delete data of a data source via a DataAdapter. A DataAdapter is a bridge between a dataset and the connection. It uses Command Object to execute SQL queries and stored procedures.All data providers share the ADO.NET common components. These components represent the data. Some of the common components are DataSet, DataView, and DataViewManager. The DataSet uses XML to store and transfer data between the applications and the data provider. A DataSet is a set of DataTable objects. A DataTable represents a database table. The DataView and DataViewManager objects provide single or multiple views of a dataset. You can attach a DataView or a DataViewManager directly to data–bound controls such as a DataGrid or DataList. Other common components are DataTable, DataRow, DataColumn and so on. Now, I'll break down the ADO.NET model to show how it works.