ABAP Select data from SAP table WRF_CLASS into internal table

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Below is a number of ABAP code snippets to demonstrate how to select data from SAP WRF_CLASS table and store it within an internal table, including using the newer @DATA inline declaration methods. It also shows you various ways to process this data using ABAP work area, inline declaration or field symbols including executing all the relevant CONVERSION_EXIT routines specific to WRF_CLASS. See here for more generic Select statement tips.

Sometimes data within SAP is stored within the database table in a different format to what it is displayed to the user. These input/output conversation FM routines are what translates the data between the two formats.

There is also a full declaration of the WRF_CLASS table where each field has a char/string type for you to simply copy and paste. This allows you to use processing that is only available to these field types such as the CONCATENATE statement.

DATA: IT_WRF_CLASS TYPE STANDARD TABLE OF WRF_CLASS,
      WA_WRF_CLASS TYPE WRF_CLASS,
      GD_STR TYPE STRING.

DATA: lo_typedescr type REF TO cl_abap_typedescr.
DATA: lv_fieldname type fieldname.

FIELD-SYMBOLS: <FIELD> TYPE any.
FIELD-SYMBOLS: <WRF_CLASS> TYPE WRF_CLASS.

*Process all fields in table header/work area as string values
  PERFORM process_as_string_field_values CHANGING wa_WRF_CLASS.

SELECT *
*restrict ABAP select to first 10 rows
 UP TO 10 ROWS      
  FROM WRF_CLASS
  INTO TABLE IT_WRF_CLASS.

*Select data and declare internal table using in-line method @DATA
*SELECT *
*  FROM WRF_CLASS
*  INTO TABLE @DATA(IT_WRF_CLASS2).
*--Further methods of using ABAP code to  select data from SAP database tables

*You can also declare the header/work area using the in-line DATA declaration method
READ TABLE IT_WRF_CLASS INDEX 1 INTO DATA(WA_WRF_CLASS2).


*Demonstrate how to loop at an internal table and update values using a FIELD-SYMBOL
LOOP AT IT_WRF_CLASS ASSIGNING <WRF_CLASS>.

*To update a field value using a field symbol simply change the value via the field symbol pointer
<WRF_CLASS>-STUFE = 1.
<WRF_CLASS>-MARKI = 1.
<WRF_CLASS>-UKLAS = 1.
<WRF_CLASS>-EKLAS = 1.
<WRF_CLASS>-MKLAS = 1.

ENDLOOP.

LOOP AT IT_WRF_CLASS INTO WA_WRF_CLASS.
*Write horizonal line to screen report.
  WRITE:/ sy-uline.

*Write selected data to screen/report before conversion.
  WRITE:/ sy-vline,   WA_WRF_CLASS-CLAS1, sy-vline,
  WA_WRF_CLASS-CLIN1, sy-vline,
  WA_WRF_CLASS-CLAS2, sy-vline,
  WA_WRF_CLASS-CLIN2, sy-vline,
  WA_WRF_CLASS-CLTX1, sy-vline,
  WA_WRF_CLASS-CLTX2, sy-vline.
ENDLOOP.
   
*Add any further fields from structure WA_WRF_CLASS you want to display...

  WRITE:/ sy-uline.
* Aternatively use generic code to Write field values (and NAME) to screen report
  DO.
    ASSIGN COMPONENT sy-index OF STRUCTURE wa_WRF_CLASS TO <field>.
    IF sy-subrc <> 0. EXIT. ENDIF.
    WRITE:/ 'Field Value', <field>, sy-vline.
    gd_str = <field> .
    lo_typedescr ?= CL_ABAP_DATADESCR=>DESCRIBE_BY_DATA( <field> ).
    lv_fieldname = lo_typedescr->GET_RELATIVE_NAME( ).
    WRITE:/ 'Field Name', lv_fieldname.
  ENDDO.

  
*Redo loop but convert all fields from internal to out value  
LOOP AT IT_WRF_CLASS INTO WA_WRF_CLASS.


*Write horizonal line to screen report.
  WRITE:/ sy-uline.

*Convert all fields to display/output versions using conversion routines
  PERFORM convert_all_field_values CHANGING wa_EKKO.
	 
ENDLOOP.

  
*&---------------------------------------------------------------------*
*& Form convert_all_field_values
*&---------------------------------------------------------------------*
FORM convert_all_field_values CHANGING p_EKKO LIKE wa_EKKO.
DATA: ld_input(1000) TYPE c, ld_output(1000) TYPE C.
ENDFORM. 

*&---------------------------------------------------------------------*
*& Form process_as_string_field_values
*&---------------------------------------------------------------------*
FORM process_as_string_field_values CHANGING p_EKKO LIKE wa_EKKO.

TYPES: BEGIN OF T_WRF_CLASS_STR, 
STUFE TYPE STRING,
MARKI TYPE STRING,
UKLAS TYPE STRING,
EKLAS TYPE STRING,
MKLAS TYPE STRING,
CLAS1 TYPE STRING,
CLIN1 TYPE STRING,
CLAS2 TYPE STRING,
CLIN2 TYPE STRING,
CLTX1 TYPE STRING,
CLTX2 TYPE STRING,
KLART TYPE STRING,
WWSKZ TYPE STRING,
VARKLART TYPE STRING,END OF T_EKKO_STR.
DATA: WA_WRF_CLASS_STR type T_EKKO_STR.

DATA: ld_text TYPE string.

LOOP AT IT_EKKO INTO WA_EKKO.
  MOVE-CORRESPONDING wa_EKKO TO WA_EKKO_STR.
  CONCATENATE: sy-vline
WA_WRF_CLASS_STR-STUFE sy-vline 
WA_WRF_CLASS_STR-MARKI sy-vline 
WA_WRF_CLASS_STR-UKLAS sy-vline 
WA_WRF_CLASS_STR-EKLAS sy-vline 
WA_WRF_CLASS_STR-MKLAS sy-vline 
WA_WRF_CLASS_STR-CLAS1 sy-vline 
WA_WRF_CLASS_STR-CLIN1 sy-vline 
WA_WRF_CLASS_STR-CLAS2 sy-vline 
WA_WRF_CLASS_STR-CLIN2 sy-vline 
WA_WRF_CLASS_STR-CLTX1 sy-vline 
WA_WRF_CLASS_STR-CLTX2 sy-vline 
WA_WRF_CLASS_STR-KLART sy-vline 
WA_WRF_CLASS_STR-WWSKZ sy-vline 
WA_WRF_CLASS_STR-VARKLART sy-vline      INTO ld_text SEPARATED BY SPACE.

*Add any further fields from structure WA_EKKO_STR you want to CONCATENATE...
ENDLOOP.
ENDFORM.