In .Net to communicate with data sources we are provided with a technology ADO.Net. ADO Stands for ActiveX Data Object. This is a collection of managed providers to speak with any data source from .net application.
When .Net was introduced to speak with data sources the best of traditional three technologies, ADO’s has been re-designed as ADO.Net
ADO.Net provides various classes which can be used for data source communication under the following Namespaces.
1. System.Data :
Collection of classes used for holding and managing data on the client machine. Classes under this are DataSet,DataTable,DataColumn,DataRow,DataView,DataRelation
2. System.Data.OLEDB : Collection of Classes used for communication with any data source.
3. System.Data.SqlClient : Collection of classes used for communication only with Sql Server.
4. System.Data.OracleClient : Collection of classes used for communication only with Oracle.
5. System.Data.ODBC : Collection of classes used for communication with traditional ODBC Drivers which will in turn Communication with Data Source.
All the above Namespaces contains same set of classes as following: Connection,Command,DataReader, DataAdapter, CommandBuilder,Parameter
Note : Each class was referred by prefixing with the NameSpace before class name to discriminate between each other as following.
- Oledb connection - Oledb Command
- Sql Connection - SqlCommand
- OracleConnection - OracleCommand
- ODBCConnection - ODBCCommand