ABAP Select data from SAP table WLK1_U into internal table

Get Example source ABAP code based on a different SAP table
  Get ABAP code

Below is a number of ABAP code snippets to demonstrate how to select data from SAP WLK1_U 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 WLK1_U. 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 WLK1_U 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_WLK1_U TYPE STANDARD TABLE OF WLK1_U,
      WA_WLK1_U TYPE WLK1_U,
      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: <WLK1_U> TYPE WLK1_U.

*Process all fields in table header/work area as string values
  PERFORM process_as_string_field_values CHANGING wa_WLK1_U.

SELECT *
*restrict ABAP select to first 10 rows
 UP TO 10 ROWS      
  FROM WLK1_U
  INTO TABLE IT_WLK1_U.

*Select data and declare internal table using in-line method @DATA
*SELECT *
*  FROM WLK1_U
*  INTO TABLE @DATA(IT_WLK1_U2).
*--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_WLK1_U INDEX 1 INTO DATA(WA_WLK1_U2).


*Demonstrate how to loop at an internal table and update values using a FIELD-SYMBOL
LOOP AT IT_WLK1_U ASSIGNING <WLK1_U>.

*To update a field value using a field symbol simply change the value via the field symbol pointer
<WLK1_U>-MANDT = 1.
<WLK1_U>-FILIA = 1.
<WLK1_U>-ARTNR = 1.
<WLK1_U>-VRKME = 1.
<WLK1_U>-DATBI = 1.

ENDLOOP.

LOOP AT IT_WLK1_U INTO WA_WLK1_U.
*Write horizonal line to screen report.
  WRITE:/ sy-uline.

*Write selected data to screen/report before conversion.
  WRITE:/ sy-vline,   WA_WLK1_U-LFDNR, sy-vline,
  WA_WLK1_U-DATAB, sy-vline,
  WA_WLK1_U-URSAC, sy-vline,
  WA_WLK1_U-QUELL, sy-vline,
  WA_WLK1_U-PFLKN, sy-vline,
  WA_WLK1_U-ANZAL, sy-vline.
ENDLOOP.
   
*Add any further fields from structure WA_WLK1_U 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_WLK1_U 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_WLK1_U INTO WA_WLK1_U.


*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.

*Conversion exit ALPHA, internal->external for field FILIA
CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
  EXPORTING
    input =                      WA_WLK1_U-FILIA
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_WLK1_U-FILIA.
WRITE:/ 'New Value:', ld_input.

*Conversion exit MATN1, internal->external for field ARTNR
CALL FUNCTION 'CONVERSION_EXIT_MATN1_OUTPUT'
  EXPORTING
    input =                      WA_WLK1_U-ARTNR
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_WLK1_U-ARTNR.
WRITE:/ 'New Value:', ld_input.

*Conversion exit CUNIT, internal->external for field VRKME
CALL FUNCTION 'CONVERSION_EXIT_CUNIT_OUTPUT'
  EXPORTING
    input =                      WA_WLK1_U-VRKME
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_WLK1_U-VRKME.
WRITE:/ 'New Value:', ld_input.

*Conversion exit ALPHA, internal->external for field URSAC
CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
  EXPORTING
    input =                      WA_WLK1_U-URSAC
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_WLK1_U-URSAC.
WRITE:/ 'New Value:', ld_input.

*Conversion exit ALPHA, internal->external for field AKTIO
CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
  EXPORTING
    input =                      WA_WLK1_U-AKTIO
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_WLK1_U-AKTIO.
WRITE:/ 'New Value:', ld_input.

*Conversion exit ALPHA, internal->external for field LIFNR
CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
  EXPORTING
    input =                      WA_WLK1_U-LIFNR
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_WLK1_U-LIFNR.
WRITE:/ 'New Value:', ld_input.

*Conversion exit MATN1, internal->external for field STRNR
CALL FUNCTION 'CONVERSION_EXIT_MATN1_OUTPUT'
  EXPORTING
    input =                      WA_WLK1_U-STRNR
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_WLK1_U-STRNR.
WRITE:/ 'New Value:', ld_input.
ENDFORM. 

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

TYPES: BEGIN OF T_WLK1_U_STR, 
MANDT TYPE STRING,
FILIA TYPE STRING,
ARTNR TYPE STRING,
VRKME TYPE STRING,
DATBI TYPE STRING,
LFDNR TYPE STRING,
DATAB TYPE STRING,
URSAC TYPE STRING,
QUELL TYPE STRING,
PFLKN TYPE STRING,
ANZAL TYPE STRING,
DATAE TYPE STRING,
NEGAT TYPE STRING,
AKTIO TYPE STRING,
THEMA TYPE STRING,
STRLI TYPE STRING,
SSTAT TYPE STRING,
LIFNR TYPE STRING,
STRNR TYPE STRING,
DATBI_OLD TYPE STRING,
LFDNR_OLD TYPE STRING,END OF T_EKKO_STR.
DATA: WA_WLK1_U_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_WLK1_U_STR-MANDT sy-vline 
WA_WLK1_U_STR-FILIA sy-vline 
WA_WLK1_U_STR-ARTNR sy-vline 
WA_WLK1_U_STR-VRKME sy-vline 
WA_WLK1_U_STR-DATBI sy-vline 
WA_WLK1_U_STR-LFDNR sy-vline 
WA_WLK1_U_STR-DATAB sy-vline 
WA_WLK1_U_STR-URSAC sy-vline 
WA_WLK1_U_STR-QUELL sy-vline 
WA_WLK1_U_STR-PFLKN sy-vline 
WA_WLK1_U_STR-ANZAL sy-vline 
WA_WLK1_U_STR-DATAE sy-vline 
WA_WLK1_U_STR-NEGAT sy-vline 
WA_WLK1_U_STR-AKTIO sy-vline 
WA_WLK1_U_STR-THEMA sy-vline 
WA_WLK1_U_STR-STRLI sy-vline 
WA_WLK1_U_STR-SSTAT sy-vline 
WA_WLK1_U_STR-LIFNR sy-vline 
WA_WLK1_U_STR-STRNR sy-vline 
WA_WLK1_U_STR-DATBI_OLD sy-vline 
WA_WLK1_U_STR-LFDNR_OLD sy-vline      INTO ld_text SEPARATED BY SPACE.

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