定义INTERNAL TABEL的要求

 

定义与ITAB内表具有相同field时

ITAB과 OTAB은 동일한 필드를 가지고 있는데 왜 위와같이 정의를 내렸는지..

SDSK不让使用的方法 ：

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DATA : BEGIN OF ITAB OCCURS 100,

            REQNO                      LIKE ZEX16-REQNO,

            NEGOID                     LIKE ZEX18-NEGOID,

             LIFNR                        LIKE ZEX16-LIFNR,

            NAME1                      LIKE LFA1-NAME1,

             CTIME                        LIKE ZEX01-CTIME,

             CTIME                        LIKE ZEX01-CTIME,

END OF ITAB.

DATA : BEGIN OF OTAB OCCURS 100,

            REQNO                      LIKE ZEX16-REQNO,

            NEGOID                     LIKE ZEX18-NEGOID,

             LIFNR                        LIKE ZEX16-LIFNR,

            NAME1                      LIKE LFA1-NAME1,

             CTIME                        LIKE ZEX01-CTIME,

             CTIME                        LIKE ZEX01-CTIME,

END OF OTAB.

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上面的定义方法会占用一些不必要的内存

SDSK 要求使用的方法：

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DATA : BEGIN OF ITAB OCCURS 100,

            REQNO                      LIKE ZEX16-REQNO,

            NEGOID                     LIKE ZEX18-NEGOID,

             LIFNR                        LIKE ZEX16-LIFNR,

            NAME1                      LIKE LFA1-NAME1,

             CTIME                        LIKE ZEX01-CTIME,

             CTIME                        LIKE ZEX01-CTIME,

END OF ITAB.

DATA: OTAB LIKE ITAB OCCURS 100 WITH HEADER LINE.

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