ADO.NET Tutorialprovides basic and advanced concepts of C# for beginners and professionals.

  1. Home
  2. ADO.NET Tutorial

Introduction to ADO.NET

Back to: ADO.NET Tutorial

ADO.NET (ActiveX Data Objects for .NET) is a data access technology from Microsoft's .NET Framework. It provides a set of classes that facilitate the communication between an application and a data source, such as a database. ADO.NET is part of the base class library in the .NET Framework and is primarily used to access relational databases, such as SQL Server, Oracle, MySQL, and others.

Key Components of ADO.NET:

  1. Data Providers: ADO.NET provides a set of data provider classes that allow you to interact with different types of data sources. The most common data providers are:

    • SQL Server Data Provider (System.Data.SqlClient): Used for SQL Server databases.
    • OLE DB Data Provider (System.Data.OleDb): Used to access databases via OLE DB.
    • ODBC Data Provider (System.Data.Odbc): Used to access databases via ODBC.
    • Oracle Data Provider (Oracle.DataAccess.Client): Used for Oracle databases.

  2. Connection Object:

    • Represents a connection to a data source (e.g., a SQL Server database).
    • Example: SqlConnection is used to connect to a SQL Server database.

  3. Command Object:

    • Represents a SQL command or stored procedure that is executed against the data source.
    • Example: SqlCommand is used to execute queries against a SQL Server database.

  4. DataReader:

    • Provides a forward-only, read-only stream of data from the database. It is an efficient way to retrieve data as it consumes less memory.
    • Example: SqlDataReader is used to read data from a SQL Server database.

  5. DataAdapter:

    • Acts as a bridge between a DataSet and a data source for retrieving and saving data.
    • It fills a DataSet with data from the data source and can also update the data source with changes made in the DataSet.

  6. DataSet:

    • Represents an in-memory cache of data retrieved from a data source. It is disconnected from the database and can hold multiple tables and relationships.
    • A DataSet can be manipulated in memory and later updated in the database.

  7. DataTable:

    • A single table of in-memory data in the DataSet. You can work with rows and columns in a DataTable just like you would in a database table.

Example of Basic ADO.NET Workflow:

  1. Establish a connection to the database using SqlConnection.
  2. Create a SqlCommand to execute a query.
  3. Use a SqlDataReader to retrieve the data from the database.
  4. Optionally, fill a DataSet with data using a SqlDataAdapter.

Code Example:

Here's a basic example of using ADO.NET to retrieve data from a SQL Server database:

using System;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        // Connection string to the database
        string connectionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=Username;Password=Password";
        
        // Query to execute
        string query = "SELECT * FROM Customers";
        
        // Using SqlConnection to connect to the database
        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            SqlCommand command = new SqlCommand(query, connection);
            connection.Open();
            
            using (SqlDataReader reader = command.ExecuteReader())
            {
                while (reader.Read())
                {
                    Console.WriteLine($"Customer ID: {reader["CustomerID"]}, Name: {reader["ContactName"]}");
                }
            }
        }
    }
}

Benefits of ADO.NET:

  • Disconnected Architecture: ADO.NET allows you to work with data in a disconnected manner using the DataSet, reducing the load on the database server.
  • Performance: ADO.NET is highly efficient, especially when working with forward-only streams of data via DataReader.
  • Scalability: It is designed for scalability, allowing multiple users to access data without overwhelming the server.

Use Cases:

  • Accessing data from relational databases.
  • Performing CRUD (Create, Read, Update, Delete) operations on a database.
  • Working with large datasets in memory using DataSet.
  • Integration with enterprise-level applications.

This introduction gives you a foundational understanding of ADO.NET and how it plays a critical role in the .NET ecosystem for data access.

Scroll to Top