Introduction To ADO.Net | Data Accessing Layer

ADO.NET is a .NET data access technology.

ADO.NET is an integral part of the .NET Compact Framework, providing access to relational data, XML documents, and application data. ADO.NET supports a variety of development needs. You can create database-client applications and middle-tier business objects used by applications, tools, languages or Internet browsers.

ADO.NET defines DataSet and DataTable objects which are optimized for moving disconnected sets of data across intranets and Internets, including through firewalls. It also includes the traditional Connection and Command objects, as well as an object called a DataReader that resembles a forward-only, read-only ADO recordset. If you create a new application, your application requires some form of data access most of the time.

ADO.NET provides data access services in the Microsoft .NET platform.


You can use ADO.NET to access data by using the new .NET Framework data providers which are:

• Data Provider for SQL Server (System.Data.SqlClient).
• Data Provider for OLEDB (System.Data.OleDb).
• Data Provider for ODBC (System.Data.Odbc).
• Data Provider for Oracle (System.Data.OracleClient).

ADO.NET is a set of classes that expose data access services to the .NET developer. The ADO.NET classes are found in System.Data.dll and are integrated with the XML classes in System.Xml.dll.

There are two central components of ADO.NET classes: the DataSet, and the .NET Framework Data Provider.

Data Provider is a set of components including:

• the Connection object (SqlConnection, OleDbConnection, OdbcConnection, OracleConnection)
• the Command object (SqlCommand, OleDbCommand, OdbcCommand, OracleCommand)
• the DataReader object (SqlDataReader, OleDbDataReader, OdbcDataReader, OracleDataReader)
• and the DataAdapter object (SqlDataAdapter, OleDbDataAdapter, OdbcDataAdapter, OracleDataAdapter).

DataSet object represents a disconnected cache of data which is made up of DataTables and DataRelations that represent the result of the command.