ABAP语言中如何定义嵌套内表(nested internal table)详解编程语言

REPORT ztest_deep_it. 
TYPES: BEGIN OF ty_po, 
         bukrs  TYPE bukrs,          "Company Code 
         podata TYPE ekko_tty,       "PO Data 
       END OF ty_po. 
DATA:git_po TYPE STANDARD TABLE OF ty_po WITH HEADER LINE. 
DATA:gwa_podata TYPE ekko. 
git_po-bukrs = '0001'. 
 
SELECT * 
  INTO TABLE git_po-podata 
  FROM ekko 
 UP TO 10 ROWS. 
 
APPEND git_po. 
 
LOOP AT git_po. 
  WRITE:git_po-bukrs. 
  LOOP AT git_po-podata INTO gwa_podata. 
    WRITE:/ gwa_podata-ebeln. 
  ENDLOOP. 
ENDLOOP.