Differences between Work Area and Field Symbol in SAP ABAP.

What are the differences between Work Area and Field Symbol?

Differences between Work Area and Field Symbol in SAP ABAP.

Work Area

Field Symbol

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1. It is the data variable.

1. It is a Pointer.

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2. The ABAP statement is DATA is used to declare

or define work areas.

2. The ABAP statement FIELD-SYMBOLS is used to declare Field symbols.

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3. The ABAP statement INTO is used to process record by record through work area .

3. The ABAP statement ASSIGNING is used to assign the FIELD-SYMBOLS .

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4. The ABAP statement MODIFY must be used to

modify the internal table .

4.No need to use MODIFY , Since it is a pointer .

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5. No need to specify within the Angular brackets (< >).

5. It Must be specify within the Angular brackets (< >) .

Field Symbol - Dynamic Programming in ABAP.

A. How to declare field symbol in sap abap.
DATA :new_val TYPE i VALUE 4.
FIELD-SYMBOLS:<lv_var> TYPE i.
ASSIGN new_val to <lv_var>.
   WRITE: / <lv_var>.
     <lv_var> = 8.
   WRITE: / new_val.
***End how to declare field symbol

B. Field symbol as a replacement of Work area in sap abap:
DATA:IT_SPFLI TYPE STANDARD TABLE OF SPFLI.
FIELD-SYMBOLS:<FS_SPFLI> TYPE SPFLI.
START-OF-SELECTION.
SELECT *
  FROM SPFLI
  INTO TABLE IT_SPFLI
  UP TO 10 ROWS.
END-OF-SELECTION.
****Loop declare
  LOOP AT IT_SPFLI ASSIGNING <FS_SPFLI>.
     <FS_SPFLI>-COUNTRYFR = 'COUNTRYFR'.
  ENDLOOP.
****End field symbol as a replacement of Work area:
***************************************************
*                      3                          *
***************************************************
C. Appending to internal table in sap abap:
DATA:IT_SPFLI1 TYPE STANDARD TABLE OF SPFLI.
FIELD-SYMBOLS:<FS_SPFLI1> TYPE SPFLI.
APPEND INITIAL LINE TO IT_SPFLI1 ASSIGNING <FS_SPFLI1>.
  IF <FS_SPFLI1> is ASSIGNED.
    <Fs_spfLi1>-COUNTRYFR = 'TEST'.
    <Fs_spfli1>-CITYFROM = 'TEST'.
    UNASSIGN <FS_SPFLI1>.
  ENDIF.

APPEND INITIAL LINE TO IT_SPFLI1 ASSIGNING <FS_SPFLI1>.
  IF <FS_SPFLI1> is ASSIGNED.
    <Fs_spfLi1>-COUNTRYFR = 'TEST1'.
    <Fs_spfli1>-CITYFROM = 'TEST1'.
    UNASSIGN <FS_SPFLI1>.
ENDIF.
*******************End appending to internal table:
**************************************************
*                      5                          *
***************************************************

D. Reading internal table using generic field symbol in sap abap:

FIELD-SYMBOLS: <fs_tab> TYPE SPFLI.
FIELD-SYMBOLS: <fs_str> TYPE SPFLI.
DATA: lt_ SPFLI TYPE STANDARD TABLE OF SPFLI.

ASSIGN lt_SPFLI TO <fs_tab>.
SELECT * FROM SPFLI INTO TABLE lt_SPFLI UP TO 10 ROWS.

READ TABLE <fs_tab> ASSIGNING <fs_str> WITH KEY ('CARRID') = 'TESTDATA'.

**************************************************
*                      6                          *
***************************************************
E. Simple Object In fields symbols
*REPORT ZSW_FIELD_SYMBOLS.
***Type declare
TYPES:BEGIN OF TY_SPFLI,
        CARRID TYPE  S_CARR_ID,
        CONNID TYPE  S_CONN_ID,
  END OF TY_SPFLI.
**Internal Table Declare.
  DATA:it_SPFLI_1 TYPE STANDARD TABLE OF TY_SPFLI.

  DATA: gd_index TYPE string,
        gd_rfp0 TYPE string.
**field Symbol  Declare
  FIELD-SYMBOLS :<fs_SPFLI_1> TYPE TY_SPFLI.
** Start selection screen
  START-OF-SELECTION.
**** Select query for fetch data
  SELECT CARRID
         CONNID
    FROM SPFLI
    INTO TABLE it_SPFLI_1
    UP TO 50 ROWS.
  END-OF-SELECTION.
**  End selection screen
*** Loop With field Symbol
  LOOP AT it_SPFLI1 ASSIGNING <fs_SPFLI>.
    IF <fs_SPFLI_1> is ASSIGNED.
       WRITE: <fs_SPFLI_1>-CARRID,<fs_SPFLI_1>-CONNID.
    ENDIF.
  ENDLOOP.
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