Hint: each primitive type has a default value. For example, 0 (zero) is the default value of integers
whereas space ( ' ' ) is the default value of characters.
Solution:
REPORT z_abap101_061.
TYPES:
BEGIN OF ty_line,
id TYPE c LENGTH 10,
name TYPE string,
value TYPE i,
creation_date TYPE d,
END OF ty_line.
TYPES: ty_table TYPE STANDARD TABLE OF ty_line.
*&---------------------------------------------------------------------*
*& Form count_initial_fields_of_table
*&---------------------------------------------------------------------*
* Counts how many fields are filled with their default value
*----------------------------------------------------------------------*
* -->US_TABLE internal table
*----------------------------------------------------------------------*
FORM count_initial_fields_of_table USING us_table TYPE ty_table.
DATA lwa_line TYPE ty_line.
DATA lv_initial_field_total TYPE i.
LOOP AT us_table INTO lwa_line.
IF lwa_line-id IS INITIAL.
lv_initial_field_total = lv_initial_field_total + 1.
ENDIF.
IF lwa_line-name IS INITIAL.
lv_initial_field_total = lv_initial_field_total + 1.
ENDIF.
IF lwa_line-value IS INITIAL.
lv_initial_field_total = lv_initial_field_total + 1.
ENDIF.
IF lwa_line-creation_date IS INITIAL.
lv_initial_field_total = lv_initial_field_total + 1.
ENDIF.
ENDLOOP.
WRITE: 'Number of initial values: ', lv_initial_field_total.
NEW-LINE.
ENDFORM. "count_initial_fields_of_table
START-OF-SELECTION.
DATA itab TYPE ty_table.
DATA wa TYPE ty_line.
wa-id = '1'.
wa-name = 'John'.
wa-value = 50.
wa-creation_date = '20140727'.
APPEND wa TO itab.
CLEAR wa.
PERFORM count_initial_fields_of_table USING itab.
wa-id = '2'.
wa-name = 'Mary'.
wa-value = 20.
* wa-creation_date = ?.
APPEND wa TO itab.
CLEAR wa.
PERFORM count_initial_fields_of_table USING itab.
wa-id = '3'.
wa-name = 'Max'.
* wa-value = ?.
* wa-creation_date = ?.
APPEND wa TO itab.
CLEAR wa.
PERFORM count_initial_fields_of_table USING itab.
wa-id = '4'.
* wa-name = ?.
* wa-value = ?.
* wa-creation_date = ?.
APPEND wa TO itab.
CLEAR wa.
PERFORM count_initial_fields_of_table USING itab.



Serkan AKKAVAK
Computer Engineer
ABAP Developer & SAP S/4 HANA Logistics Consultant
Contact : serkurumsal@yandex.com