ABAP Select data from SAP table VNCTX into internal table

Get Example source ABAP code based on a different SAP table
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Below is a number of ABAP code snippets to demonstrate how to select data from SAP VNCTX 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 VNCTX. 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 VNCTX 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_VNCTX TYPE STANDARD TABLE OF VNCTX,
      WA_VNCTX TYPE VNCTX,
      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: <VNCTX> TYPE VNCTX.

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

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

*Select data and declare internal table using in-line method @DATA
*SELECT *
*  FROM VNCTX
*  INTO TABLE @DATA(IT_VNCTX2).
*--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_VNCTX INDEX 1 INTO DATA(WA_VNCTX2).


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

*To update a field value using a field symbol simply change the value via the field symbol pointer
<VNCTX>-MANDT = 1.
<VNCTX>-CXID = 1.
<VNCTX>-CXTYP = 1.
<VNCTX>-STDEF = 1.
<VNCTX>-CXSTA = 1.

ENDLOOP.

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

*Write selected data to screen/report before conversion.
  WRITE:/ sy-vline,   WA_VNCTX-CXVALD, sy-vline,
  WA_VNCTX-CXRSP, sy-vline,
  WA_VNCTX-ERDAT, sy-vline,
  WA_VNCTX-ERUSR, sy-vline,
  WA_VNCTX-UPDAT, sy-vline,
  WA_VNCTX-UPUSR, sy-vline.
ENDLOOP.
   
*Add any further fields from structure WA_VNCTX 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_VNCTX 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_VNCTX INTO WA_VNCTX.


*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 CXRSP
CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
  EXPORTING
    input =                      WA_VNCTX-CXRSP
  IMPORTING
    output =                     ld_input.
WRITE:/ 'Org Value:', WA_VNCTX-CXRSP.
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_VNCTX_STR, 
MANDT TYPE STRING,
CXID TYPE STRING,
CXTYP TYPE STRING,
STDEF TYPE STRING,
CXSTA TYPE STRING,
CXVALD TYPE STRING,
CXRSP TYPE STRING,
ERDAT TYPE STRING,
ERUSR TYPE STRING,
UPDAT TYPE STRING,
UPUSR TYPE STRING,
STORN TYPE STRING,
STUSR TYPE STRING,
STDAT TYPE STRING,
KZ TYPE STRING,END OF T_EKKO_STR.
DATA: WA_VNCTX_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_VNCTX_STR-MANDT sy-vline 
WA_VNCTX_STR-CXID sy-vline 
WA_VNCTX_STR-CXTYP sy-vline 
WA_VNCTX_STR-STDEF sy-vline 
WA_VNCTX_STR-CXSTA sy-vline 
WA_VNCTX_STR-CXVALD sy-vline 
WA_VNCTX_STR-CXRSP sy-vline 
WA_VNCTX_STR-ERDAT sy-vline 
WA_VNCTX_STR-ERUSR sy-vline 
WA_VNCTX_STR-UPDAT sy-vline 
WA_VNCTX_STR-UPUSR sy-vline 
WA_VNCTX_STR-STORN sy-vline 
WA_VNCTX_STR-STUSR sy-vline 
WA_VNCTX_STR-STDAT sy-vline 
WA_VNCTX_STR-KZ sy-vline      INTO ld_text SEPARATED BY SPACE.

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