7.ADO.net Data Providers

7/29/2019 7.ADO.net Data Providers

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ADO.NET Data Provider


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Agenda

Introduction to ADO.NET

ADO.NET Architecture

Objects in ADO.NET

.NET Data Providers

Connecting to Data Base (SQLServer)

Properties and Methods of the

SqlConnection Class

Storing Connection Strings in theConfiguration File

Using Command Object

Creating Command Object

Executing a Command That Doesn'tReturn Rows.

Executing a Command That Returnsa Single Value.

Parameterized Command

Using DataReader Object

Transactions

Transaction Demo.


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Introduction to ADO.NET

ADO.NET is a data-access subsystem in the Microsoft .NET Framework.

ADO.NET was developed from ADO (ActiveX Data Objects).

In the .NET Framework, the ADO.NET libraries appear under theSystem.Data namespace.

Supports both connected and disconnected data access.


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ADO.NET Architecture


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Objects in ADO.NET

Connected Objects

Connection

Transaction

Command

Parameter

DataReader

DataAdapter

Disconnected Objects

Dataset

DataTable

DataRow

DataColumn

DataView

Constraint


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.NET Data Providers

The .NET data provider is the managed component of choice for databasevendors to expose their data in the most effective way.

Each database vendor should provide a .NET-compatible API that is callablefrom within managed applications.

The Data Provider is responsible for providing and maintaining the connectionto the database.


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Connecting to Data Base (SQL Server)

Creating Connection Object

By creating instance ofSqlConnection Class.

SqlConnection testConnection = new SqlConnection();

Connection String Property

SqlConnection testConnection= new SqlConnection(

"Data Source=(local);Initial Catalog=Test;Integrated Security=SSPI");

(OR)

SqlConnection testConnection = new SqlConnection();

string testConnectionString = "Data Source=(local);Initial Catalog=Test;Integrated

Security=SSPI";

testConnection.ConnectionString = testConnectionString;


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Creating and Managing Connections

To create and manage connections, you need to:Create a connection object.

Create a command object.

Open the connection object.

Execute the SQL statement in the command object.

Close the connection object.


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Storing Connection Strings in the Configuration File

For each connection string in the application, add a new element tothe element in the configuration file, as follows:

The classes for accessing the configuration file are found in theSystem.Configuration namespace.

Code below creates connection using connection string stored in configurationfile

SqlConnection MyConnection;

MyConnection = new SqlConnection();

MyConnection.ConnectionString =

ConfigurationManager.ConnectionStrings [constring].ConnectionString;


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Using Command Object

The Command object is the heart of data processing with ADO.NET.

The Command object wraps a SQL statement or a call to a stored procedure.

Properties and Methods of the SqlCommand Class


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Executing a Command That Doesn't Return Rows


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Executing a Command That Returns a Single Value


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Parameterized Command


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The SqlDataReader class defines a lightweight yet powerful object that is usedto read information from a SQL database.

SqlDataReader retrieves query results in a read-only, forward-only stream ofinformation and will not let you perform updates.


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The following code snippet illustrates the typical loop you implement to readall the records of a query:


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Thank You

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7.ADO.net Data Providers