what is Web.config ?

As name suggest web.config is web site configuration file.

Globally configure you website through web.config file.

what is view in sql server ?

view is one type of virtual table so view does not contain physical memory.

view is just some columns and rows combination which is selected from one or

more table.just it contain query.

 view benefits :- 

view is provide abstract layer over database tables. it's provide security.

only some non sensitive columns select in query so confidential data can not

appear that particular user.

for example:-

create view view_name select name from tbladmin.    

using SqlDataAdapter Update table

using System;

using System.Data;

using System.Data.SqlClient;



class UpdateusingdataobjAdapter
{
static void Main()
{
string cn="server=localhost;database=DBTEST;uid=sa;pwd=sa";
SqlConnection Connection = new SqlConnection(cn);
string query = @"select * from tblemp ";
string update = @"update tblemp set name = @name where id = @id";
try
{

   SqlDataobjAdapter objAd = new SqlDataobjAdapter();

   objAd.SelectCommand = new SqlCommand(query, Connection );
   DataSet objDs = new DataSet();  

   objAd.Fill(objDs, "tblemp");
   DataTable objDt = objDs.Tables["tblemp"];

   objDt.Rows[0]["name"] = "Ravi";

   foreach (DataRow row in objDt.Rows)
   {

    Console.WriteLine(

                  "{0} {1}",

                  row["name"].ToString(),

                  row["lastname"].ToString();

            }



     // Update tblemps

    SqlCommand objcmd = new SqlCommand(update, Connection );

    objcmd.Parameters.Add("@name",SqlDbType.NVarChar,15, "name");

    SqlParameter parm = objcmd.Parameters.objAdd("@id",SqlDbType.Int,4,"id");

    parm.SourceVersion = DataRowVersion.Original;

    objAd.UpdateCommand = objcmd;

    objAd.Update(objDs, "tblemp");

    }
catch(Exception e)
 {

            Console.WriteLine("Error: " + e);

 }
finally
 {

            Connection.Close();

 }

      } 

   }