ADO DOT NET, Connection, Command and DataReader object

ADO DOT NET (Active Data Object)

^[DEFINATION] It’s a component in dot net framework which helps us to fetch data from different data source to c# or from C# code to data sources.

ADO DOT NET comprises of 6 components:

1.      Connection- Compulsory
2.      Command - Compulsory
3.      Data Reader
4.      Data Adapter
5.      Data Set
6.      Data View

In these 6 components 2 components are compulsory (connection and command)

Connection Object - this object is needed to connect to data source like Sql-Server, Oracle, MySql etc to use this object at least two things are required.

a.       Data source- where database is located either in local host or on remote host.

b.      Security credentials -like windows authentication, user id and password.

    Command Object- Sql syntaxes are written here and it helps to execute the Sql query. 

    Data Reader -  [Connected, Read Only and Forward Only Record Set]

Data Adapter - It’s bridge between data source and dataset. It actually fills the dataset with data coming from database. 

Data Set It’s a disconnected record set which can be browsed forth and back direction and can also be updated.

Difference B/W DataReader and DataSet

#	DataReader                                                 DataSet
1.	Its collection of connected records                  Its collection of disconnected records.
2.	It can only be accessed in forward mode         It can be accessed in forward and backward mode.
3.	Records in DataReader cannot be updated      Records in DataSet can be updated.