What is the namespace in which .NET have the data functionality classes?
This namespace contains the basic objects used for accessing & storing relational data, like DataTable,DataSet, and DataRelation. Each of these is independent of the type of the data source and the way we connect to it.
This namespace contains the objects that we use to connect to a data source via an OLE-DB provider, like the OleDbCommand, OleDbConnection, etc. These objects inherit from the common base classes,& so have the similar methods,properties, and events as the SqlClient equivalents.
This namespace contains the objects that we use to connect the data source via the Tabular Data Stream (TDS) interface of the Microsoft SQL Server . This can normally give better performance as it removes some of the intermediate layers required by an OLE-DB connection.
This namespace Contains the basic objects needed to create, store, read, write, and for manipulating XML documents according to W3C recommendations.