ADO.NET

 ADO.NET Interview Questions and Answers

1.What is ADO.NET?

ADO stands for Active Data Object and ADO.NET is a set of .NET libraries for ADO.

Used to connect to database from c#.net  program.
 
ADO.NET is a collection of managed libraries used by .NET applications for data source communication using a driver or provider:

• Enterprise applications handle a large amount of data. This data is primarily stored in relational databases, such as Oracle, SQL Server, and Access and so on. These databases use Structured Query Language (SQL) for retrieval of data.

• To access enterprise data from a .NET application, an interface was needed. This interface acts as a bridge between an RDBMS system and a .NET application. ADO.NET is such an interface that is created to connect .NET applications to RDBMS systems.

• In the .NET framework, Microsoft introduced a new version of Active X Data Objects (ADO) called ADO.NET. Any .NET application, either Windows based or web based, can interact with the database using a rich set of classes of the ADO.NET library. Data can be accessed from any database using connected or disconnected architecture.

ADO.NET provides mainly the following two types of architectures:

• Connected Architecture.

• Disconnected Architecture.

2.What are the main namespaces used in ADO.NET?

ADO.NET Namespaces

System.Data->Contains the definition for columns, relations, tables, database, rows, views and constraints.

System.Data.SqlClient ->Contains the classes that are used to connect to a Microsoft SQL Server database such as SqlCommand, SqlConnection, SqlDataAdapter.

System.Data.Odbc->Contains classes required to connect to most ODBC drivers. These classes include OdbcCommand,OdbcConnection.

System.Data.OracleClient ->Contains classes such as OracleConnection,OracleCommand required to connect to an Oracle database.