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Iam not able to retrieve completely the data from sql?
public string getString()
{

  con.ConnectionString = ConnString;
  con.Open();
  string sp = "select top 3 hotelid from hotel order by NEWID()";
  SqlCommand cmd = new SqlCommand(sp, con);

  SqlDataAdapter sa = new SqlDataAdapter(cmd);
  cmd.ExecuteNonQuery();
  reader = cmd.ExecuteReader();
  while (reader.Read()) //Call Read to move to next record returned by SQL //OR call --While(reader.Read())
  {
    det  = reader[0].ToString();

  }
  reader.Close();
  con.Close();
  return det;
}

det += reader[0].ToString();

public List<string> getString()
{
  ...
  List<string> ret = new List<string>;
  while (reader.Read())
    ret.Add(reader[0].ToString());
  ...
  return ret;
}