What is the namespace in which .NET has the data functionality class?

Following are the namespaces provided by .NET for data management:

System.Data

This contains the basic objects used for accessing and storing relational data, such as DataSet, DataTable, andDataRelation. Each of these is independent of the type of data source and the way we connect to it.

System.Data.OleDB

It contains the objects that we use to connect to a data source via an OLE-DB provider, such as OleDbConnection,OleDbCommand, etc. These objects inherit from the common base classes, and so have the same properties, methods, and events as the SqlClient equivalents.

System.Data.SqlClient

This contains the objects that we use to connect to a data source via the Tabular Data Stream (TDS) interface of Microsoft SQL Server (only). This can generally provide better performance as it removes some of the intermediate layers required by an OLE-DB connection.

System.XML

This contains the basic objects required to create, read, store, write, and manipulate XML documents according to W3C recommendations.