What is the significance of the SqlDataReader?

The SqlDataReader is used to retrieve data from the database in a forward-only and

read-only manner. It is more efficient than a DataSet when you need to retrieve a large

amount of data quickly and do not need to modify the data. It requires an open connection to

the database and reads data sequentially, one row at a time.

Example:

SqlCommand command = new SqlCommand("SELECT CustomerName FROM

Customers", connection);

SqlDataReader reader = command.ExecuteReader();

while (reader.Read())

Console.WriteLine(reader["CustomerName"]);

reader.Close();