SOME COMPUTER STUFF ON C,JAVA,TALLY,BCA,SOLVED PAPERS

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.SqlClient; namespace WindowsFormsApplication1 {     class query     {      public   SqlConnection con;         SqlCommand cmd;         public SqlDataReader sdr;         public query()         {             con = new SqlConnection("Data Source=LAB1PC7\\SQLEXPRESS;Initial Catalog=Test;Integrated Security=True");         }         public int modify(string s)         {             con.Open();             cmd = new SqlCommand(s, con);             int r = cmd.ExecuteNonQuery();             con.Close();           ...