Perfomance issue with ekpo table

  SELECT ebeln bsart lifnr

         FROM ekko

         INTO TABLE t_ekko

         WHERE bsart EQ p_bsart

         AND   loekz EQ ''

         AND   frgrl EQ ''

         AND   memory EQ ''.

the below select query takes too much time. is there any other ways to get fast????

  IF t_ekko[] is not initial..

      SELECT ebeln ebelp matnr menge loekz               

             FROM ekpo

             INTO TABLE t_ekpo

             FOR ALL ENTRIES IN t_ekko

             WHERE ebeln EQ t_ekko-ebeln

             AND   elikz EQ ''

             AND   aedat NE sy-datum.

endif.