Why DataReader Useful?
Data Reader is Read only version Data Set,Each record is returned as a Data Reader Object,ExecuteReader method acts directly on the database connection. There are two versions of the data reader object: OleDbDataReader and SqlDataReader • Differnce B/w DataReader and DataSet The Dataset is an core of disconnected architecture.Disconnected architecture means once you have retriveed the data from the database the connect of the datasource is dropped.The disconnected data become very commonlyThe dataset for the disconnected data from the Dataset object.The DataReader is an readonly ,forward only stream from the database.While using the datareader can improve the application performance reduce the system overhead because only one buffer row at a time in memory.
