If you know year, month and fiscal year variant and you want to know the first date and end date of that period, you can apply function module "PERIOD_DAY_DETERMINE" in ABAP/4 to get them.

Example

CALL FUNCTION ’PERIOD_DAY_DETERMINE’
  EXPORTING
    I_GJAHR       =     ’2006’       "Year
    I_MONAT       =     ’01’         "Month
    I_PERIV       =     ’F2’         "Fiscal Year Variant

  IMPORTING
    E_FDAY        =     FIRST_DATE
    E_LDAY        =     END_DATE
  EXCEPTIONS  

You will apply this statement when you want to loop data with non-condition loops.

Example 1: Simple Loop

DO.
  WRITE:/ sy-index.
  IF sy-index = 4.
    EXIT.
  ENDIF.
ENDDO.

The output is

1
2
3
4

Example 2: Loops with n times

DO 4 TIMES.
  WRITE:/ sy-index.
ENDDO.

The output is same as example 1.

Example 3: Nested Loops

• CONTINUE
  When you apply this statement, system will pass a current loop. System  ignores any statements after CONTINUE statement and start to the next loop.

Example

DO 4 TIMES.
  WRITE:/ sy-index.
  IF sy-index <= 2.
    CONTINUE.

  ENDIF.
  WRITE: ’After’.
ENDDO.

The output is

1  
2  
3   After
4   After

• CHECK
  This statement will apply if you want to check condition before go to next statement. If the result of checking is ’TRUE’, system will go to next step as normally. If the result of checking is ’FALSE’, system will operate look like CONTINUE statement.

Example

You will apply this statement when you want to loop data with condition loops.

Example 1: Simple Loop

DATA: lv_int TYPE I VALUE 1.
WHILE lv_int <= 4.
  WRITE:/ lv_int.
  lv_int = lv_int + 1.




ENDWHILE.

The output is 

1
2
3
4

Example 3: Nested Loops

DATA: lv_int TYPE I VALUE 1,
      lv_int2 TYPE I.

WHILE lv_int <= 4.
  WRITE:/ lv_int.
  lv_int2 = 1.
  WHILE lv_int2 <= 2.
    WRITE: lv_int2.
    lv_int2 = lv_int2 + 1.
  ENDWHILE.
  lv_int = lv_int + 1.




ENDWHILE.

The output is 

Select...Where

SELECT * FORM SPFLI
  WHERE CARRID = ’LH’.
  ...
  ...
  ...
ENDSELECT.

Select...Check

SELECT * FORM SPFLI.
  CHECK SPFLI-CARRID = ’LH’.
  ...
  ...
  ...
ENDSELECT.

In above logic, Select...Where is better than Select...Check because the database can then user an index and system resource load is considerably less.

Select...Into Table

DATA: itab LIKE SPFLI OCCURS 0 WITH HEADER LINE.
SELECT * FORM SPFLI INTO TABLE itab.

Select...Append

DATA: itab LIKE SPFLI OCCURS 0 WITH HEADER LINE.
SELECT * FORM SPFLI INTO itab.
  APPEND itab.
ENDSELECT.

In above logic, Select...Into Table is faster than Select...Append.