ADO.NET

ADO.NET (ActiveX Data Objects) is set of classes that expose data access services to the .NET application.
It uses 2 types of objects to access data from database.
a. Datasets
b. .NET Data Provider Objects - Data Adapters, Commands , Connections

Dataset holds entire database int it. So we can have the data inserted, updated in it though the connection is lost from the datasource. this is referred to as Disconnected architecture.

DataAdapter serves as a bridge between dataset and a datasource for retrieving and saving data
Used to exchange data between datasource and dataset.

To trnasmit a database table of dataset to the datastore, dataadapters Update method can be used. When thos method is invoked, it executes whatever SQl INSERT, UPDATE, DELETE statements are needed depending on the affected record is new, changes or deleted.

Connection pooling enables an application to use a connection from a pool of connections that do not need to be re established for every use. Once connection has been created and placed in connection pool, application can reuse the connection without performing the complete connection creation process.