SqlConnection conn = new SqlConnection("Data Source=;Initial Catalog=;Persist Security Info=True;User ID=;Password=");
conn.Open();

SqlCommand command = new SqlCommand("Select id from [table1] where name=@zip", conn);
command.Parameters.AddWithValue("@zip","india");
 // int result = command.ExecuteNonQuery();
using (SqlDataReader reader = command.ExecuteReader())
{
  if (reader.Read())
  {
     Console.WriteLine(String.Format("{0}",reader["id"]));
   }
}

conn.Close();

DataSet ds = new DataSet();
//https://www.oracle.com/webfolder/technetwork/tutorials/obe/db/dotnet/ODPNET_Core_get_started/index.html
using (SqlConnection con = new SqlConnection(connectionstr))
{
    using (SqlCommand cmd = con.CreateCommand())
    {
        con.Open();
        cmd.CommandText = "select * from master.sys.server_principals";
        SqlDataAdapter adapter = new SqlDataAdapter(cmd);
        adapter.Fill(ds);
    }
}