DataReader

Question

Dear Frnds I want to knw about Datareader and how its different from Dataset. how we can use it in our coding an example will be helpful in understanding. Thanks & Regars Aamir

Mukesh Kumar · Answer

Hi Here are some differences between DataReader & DataSet DataSet object DataReader object Read/Write access Read-only access Supports multiple tables from different databases Supports a single table based on a single SQL query of one database Disconnected mode Connected mode Bind to multiple controls Bind to a single control Forward and backward scanning of data Forward-only scanning of data Slower access to data Faster access to data Greater overhead to enable additional features Lightweight object with very little overhead Supported by Visual Studio .NET tools Must be manually coded For more detail :http://msdn.microsoft.com/en-us/magazine/cc188717.aspx

Satyapriya Nayak · Answer

Hi Aamir DataReader provides forward-only and read-only access to data  while the DataSet object can hold more than one table (in other words more than one rowset) from the same data source as well as the relationships between them. Dataset is a disconnected architecture while datareader is connected architecture. Dataset can persists contents while datareader can not persist contents  they are forward only. Dataset Datareader example to display record in gridview. Untitled Page Text=Using Dataset /> Text=Using Datatable /> Text=Using Datareader /> using System; using System.Configuration; using System.Data; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Xml.Linq; using System.Data.OleDb; public partial class _Default : System.Web.UI.Page { OleDbConnection con; OleDbCommand com; OleDbDataAdapter oda; DataSet ds; DataTable dataTable; protected void Button1_Click(object sender EventArgs e) { con = new OleDbConnection(Provider = Microsoft.Jet.OLEDB.4.0; Data Source = D:\mydb.mdb); com = new OleDbCommand(Select * from emp con); con.Open(); oda = new OleDbDataAdapter(com); ds = new DataSet(); oda.Fill(ds emp); con.Close(); GridView1.DataMember = emp; GridView1.DataSource = ds; GridView1.DataBind(); } protected void Button2_Click(object sender EventArgs e) { con = new OleDbConnection(Provider = Microsoft.Jet.OLEDB.4.0; Data Source = D:\mydb.mdb); dataTable = new DataTable(); com = new OleDbCommand(); com.Connection = con; con.Open(); com.CommandText = Select * from emp; oda = new OleDbDataAdapter(com); oda.Fill(dataTable); con.Close(); GridView1.DataSource = dataTable; GridView1.DataMember = emp; GridView1.DataBind(); } protected void Button3_Click(object sender EventArgs e) { con = new OleDbConnection(Provider = Microsoft.Jet.OLEDB.4.0; Data Source = D:\mydb.mdb); com = new OleDbCommand(Select * from emp con); con.Open(); OleDbDataReader reader; reader = com.ExecuteReader(); GridView1.DataMember = emp; GridView1.DataSource = reader; GridView1.DataBind(); reader.Close(); con.Close(); } } Thanks If this post helps you mark it as answer