SAP/ABAP: Dinamik Query

PARAMETERS: RB_HEPSI RADIOBUTTON GROUP RAD1 DEFAULT 'X',
                 RB_CIKAN RADIOBUTTON GROUP RAD1,
                 RB_CIKMA RADIOBUTTON GROUP RAD1.
...
  CLEAR: GV_WEAKT_QUERY.
  CASE 'X'.
    WHEN RB_HEPSI.
      WRITE:
      '( EKKO~WEAKT IS NOT NULL OR EKKO~WEAKT IS NULL )'
      TO GV_WEAKT_QUERY.
    WHEN RB_CIKAN.
      WRITE: '( EKKO~WEAKT IS NOT NULL )'
      TO GV_WEAKT_QUERY.
    WHEN RB_CIKMA.
      WRITE:  '( EKKO~WEAKT IS NULL )'
      TO GV_WEAKT_QUERY.
  ENDCASE.

...

  SELECT *
    INTO CORRESPONDING FIELDS OF TABLE GT_VERI
    FROM EKKO AS EKKO
    INNER JOIN LFA1 AS LFA1
    ON EKKO~LIFNR = LFA1~LIFNR
    WHERE EKKO~AEDAT IN S_AEDAT
      AND EKKO~EKGRP IN S_EKGRP
      AND EKKO~LIFNR IN S_LIFNR
      AND (GV_WEAKT_QUERY)
      AND EKKO~BSART NE P_BSART
      AND EKKO~BSTYP EQ P_BSTYP.