ABAP Select data from SAP table KWN_NODE 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 KWN_NODE 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 KWN_NODE. 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 KWN_NODE 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_KWN_NODE TYPE STANDARD TABLE OF KWN_NODE,
      WA_KWN_NODE TYPE KWN_NODE,
      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: <KWN_NODE> TYPE KWN_NODE.

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

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

*Select data and declare internal table using in-line method @DATA
*SELECT *
*  FROM KWN_NODE
*  INTO TABLE @DATA(IT_KWN_NODE2).
*--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_KWN_NODE INDEX 1 INTO DATA(WA_KWN_NODE2).


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

*To update a field value using a field symbol simply change the value via the field symbol pointer
<KWN_NODE>-TREE_ID = 1.
<KWN_NODE>-EXTENSION = 1.
<KWN_NODE>-NODE_ID = 1.
<KWN_NODE>-EXT_KEY = 1.
<KWN_NODE>-PARENT_ID = 1.

ENDLOOP.

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

*Write selected data to screen/report before conversion.
  WRITE:/ sy-vline,   WA_KWN_NODE-BROTHER_ID, sy-vline,
  WA_KWN_NODE-REFNODE_ID, sy-vline,
  WA_KWN_NODE-REFTREE_ID, sy-vline,
  WA_KWN_NODE-NODE_TYPE, sy-vline,
  WA_KWN_NODE-LOCAL_FLAG, sy-vline,
  WA_KWN_NODE-VALID_F_R, sy-vline.
ENDLOOP.
   
*Add any further fields from structure WA_KWN_NODE 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_KWN_NODE 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_KWN_NODE INTO WA_KWN_NODE.


*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_KWN_NODE_STR, 
TREE_ID TYPE STRING,
EXTENSION TYPE STRING,
NODE_ID TYPE STRING,
EXT_KEY TYPE STRING,
PARENT_ID TYPE STRING,
BROTHER_ID TYPE STRING,
REFNODE_ID TYPE STRING,
REFTREE_ID TYPE STRING,
NODE_TYPE TYPE STRING,
LOCAL_FLAG TYPE STRING,
VALID_F_R TYPE STRING,
VALID_T_R TYPE STRING,
VALID_F_D TYPE STRING,
VALID_T_D TYPE STRING,
W_SUBNODES TYPE STRING,
APPL_FLAG1 TYPE STRING,
APPL_FLAG2 TYPE STRING,
APPL_FLAG3 TYPE STRING,
COPY_NODE TYPE STRING,
COPY_TREE TYPE STRING,
COPNODFRST TYPE STRING,
COPTREFRST TYPE STRING,
COMPONENT TYPE STRING,
SYSTEMINST TYPE STRING,
COMPRELFR TYPE STRING,
COMPRELTO TYPE STRING,
DEFAULTFLG TYPE STRING,
PRDVERSFR TYPE STRING,
PRDVERSTO TYPE STRING,
FUSER TYPE STRING,
FDATE TYPE STRING,
FTIME TYPE STRING,
FRELEASE TYPE STRING,
LUSER TYPE STRING,
LDATE TYPE STRING,
LTIME TYPE STRING,
LRELEASE TYPE STRING,END OF T_EKKO_STR.
DATA: WA_KWN_NODE_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_KWN_NODE_STR-TREE_ID sy-vline 
WA_KWN_NODE_STR-EXTENSION sy-vline 
WA_KWN_NODE_STR-NODE_ID sy-vline 
WA_KWN_NODE_STR-EXT_KEY sy-vline 
WA_KWN_NODE_STR-PARENT_ID sy-vline 
WA_KWN_NODE_STR-BROTHER_ID sy-vline 
WA_KWN_NODE_STR-REFNODE_ID sy-vline 
WA_KWN_NODE_STR-REFTREE_ID sy-vline 
WA_KWN_NODE_STR-NODE_TYPE sy-vline 
WA_KWN_NODE_STR-LOCAL_FLAG sy-vline 
WA_KWN_NODE_STR-VALID_F_R sy-vline 
WA_KWN_NODE_STR-VALID_T_R sy-vline 
WA_KWN_NODE_STR-VALID_F_D sy-vline 
WA_KWN_NODE_STR-VALID_T_D sy-vline 
WA_KWN_NODE_STR-W_SUBNODES sy-vline 
WA_KWN_NODE_STR-APPL_FLAG1 sy-vline 
WA_KWN_NODE_STR-APPL_FLAG2 sy-vline 
WA_KWN_NODE_STR-APPL_FLAG3 sy-vline 
WA_KWN_NODE_STR-COPY_NODE sy-vline 
WA_KWN_NODE_STR-COPY_TREE sy-vline 
WA_KWN_NODE_STR-COPNODFRST sy-vline 
WA_KWN_NODE_STR-COPTREFRST sy-vline 
WA_KWN_NODE_STR-COMPONENT sy-vline 
WA_KWN_NODE_STR-SYSTEMINST sy-vline 
WA_KWN_NODE_STR-COMPRELFR sy-vline 
WA_KWN_NODE_STR-COMPRELTO sy-vline 
WA_KWN_NODE_STR-DEFAULTFLG sy-vline 
WA_KWN_NODE_STR-PRDVERSFR sy-vline 
WA_KWN_NODE_STR-PRDVERSTO sy-vline 
WA_KWN_NODE_STR-FUSER sy-vline 
WA_KWN_NODE_STR-FDATE sy-vline 
WA_KWN_NODE_STR-FTIME sy-vline 
WA_KWN_NODE_STR-FRELEASE sy-vline 
WA_KWN_NODE_STR-LUSER sy-vline 
WA_KWN_NODE_STR-LDATE sy-vline 
WA_KWN_NODE_STR-LTIME sy-vline 
WA_KWN_NODE_STR-LRELEASE sy-vline      INTO ld_text SEPARATED BY SPACE.

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