public DbDataReader SqlToDbDataReader(string sql)
{
DbConnection conexion = factory.CreateConnection ();
conexion.ConnectionString = ConnectionString;
conexion.Open ();
DbCommand comando = factory.CreateCommand ();
comando.Connection = conexion;
comando.CommandType = CommandType.Text;
comando.CommandText = sql;
comando.CommandTimeout = CommandTimeOut;
return comando.ExecuteReader (CommandBehavior.CloseConnection);
}