LOOP WHERE 절 개선

- 개선전
  LOOP AT it_mseg WHERE spmon EQ p_month
                    AND werks EQ it_box-werks
                    AND charg EQ it_box-zboxno.
                                     
- 개선후
  SORT IT_MSEG_PLANT BY SPMON WERKS CHARG.  
  READ TABLE IT_MSEG_PLANT WITH KEY SPMON = P_MONTH    
                                    WERKS = IT_BOX-WERKS
                                    CHARG = IT_BOX-ZBOXNO
                                    BINARY SEARCH TRANSPORTING NO FIELDS.
  CHECK SY-SUBRC = 0.
  LOOP AT IT_MSEG_PLANT FROM SY-TABIX.
   IF IT_MSEG_PLANT-SPMON <> P_MONTH OR
      IT_MSEG_PLANT-WERKS <> IT_BOX-WERKS OR
      IT_MSEG_PLANT-CHARG <> IT_BOX-CHARG.
     EXIT.
   ENDIF.
   ....
   ....
  ENDLOOP.

READ 문 개선

- 개선전
  READ TABLE it_ztm3e300_tmp WITH KEY  werks  = it_ztm3e300-werks 
                                       zponor = it_ztm3e300-zponor.
                                      
- 개선후
  SORT IT_ZTM3E300_TMP BY WERKS ZPONOR. <= 추가
  READ TABLE it_ztm3e300_tmp WITH KEY werks  = it_ztm3e300_plant-werks
                                      zponor = it_ztm3e300_plant-zponor
                                      BINARY SEARCH. <= 추가

MODIFY 문 개선

- 개선전
  MODIFY it_hub50 TRANSPORTING wruser wrdate wrtime wrstatus
                         WHERE bukrs  = w_hub50-bukrs
                           AND sndate = w_hub50-sndate
                           AND trnscd = w_hub50-trnscd
                          
- 개선후
  내부테이블을 SORTED TABLE 로 선언

DELETE 문 개선

- 개선전
  LOOP AT IT_DEL
    DELETE it_010  WHERE lotno = it_del-lotno.
    DELETE it_011  WHERE lotno = it_del-lotno.
  ENDLOOP
 
- 개선후
  READ TABLE IT_010 WITH KEY LOTNO = IT_DEL-LOTNO
                             BINARY SEARCH TRANSPORTING NO FIELDS.
  LOOP AT IT_010 FROM SY-TABIX.
    IF IT_010-LOTNO <> IT_DEL-LOTNO.
      EXIT.
    ENDIF.
    DELETE IT_010.
  ENDLOOP.

Nested Loops

DATA : IVBAK LIKE VBAK OCCURS 0,
       IVBAP LIKE VBAP OCCURS 0.

SORT : IVBAK BY VBELN,
       IVBAP BY VBELN.
      
- 개선전
  LOOP AT IVBAK.
    LOOP AT IVBAP WHERE VBELN = VBAK-VBELN.
      WRITE:/ IVBAK-VBELN, IVBAP-VBPOS, ...
    ENDLOOP.
 ENDLOOP.

- 개선후
  LOOP AT IVBAK.
    READ TABLE IVBAP WITH KEY VBELN = IVBAK-VBELN
                     BINARY SEARCH TRANSPORTING NO FIELDS.
    LOOP AT IVBAP FROM SY-TABIX.
      IF IVBAP-VBELN <> IVBAK-VBELN.
        EXIT.
      ENDIF.
      WRITE:/ IVBAK-VBELN, IVBAP-VBPOS, ...
    ENDLOOP.
  ENDLOOP.