ABAP Change Documents: Logging Data Changes

Change Document Concepts

Concept	Description
Change document object	Definition of tables to be logged
Change document	Individual log entry
CDHDR	Header table for change documents
CDPOS	Item table (field changes)

Important Transactions

Transaction	Description
SCDO	Maintain change document objects
SCU3	Display change documents (generic)
RSSCD100	Evaluate change documents

Basic Examples

Write Change Document

DATA: ls_order_old TYPE zorder,
      ls_order_new TYPE zorder,
      lv_objectid  TYPE cdhdr-objectid.

" Read old data (before change)
SELECT SINGLE * FROM zorder INTO ls_order_old
  WHERE order_id = '1000000001'.

" Set new data
ls_order_new = ls_order_old.
ls_order_new-status = 'C'.  " Changed
ls_order_new-amount = 1500.

" Object ID for change document
lv_objectid = ls_order_old-order_id.

" Open change document
CALL FUNCTION 'CHANGEDOCUMENT_OPEN'
  EXPORTING
    objectclass = 'ZORDER'
    objectid    = lv_objectid
    planned_change_number = ' '
    planned_or_real_changes = 'R'.

" Log changes
CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
  EXPORTING
    tablename       = 'ZORDER'
    workarea_old    = ls_order_old
    workarea_new    = ls_order_new
    change_indicator = 'U'.  " Update

" Close and save change document
CALL FUNCTION 'CHANGEDOCUMENT_CLOSE'
  EXPORTING
    objectclass      = 'ZORDER'
    objectid         = lv_objectid
    date_of_change   = sy-datum
    time_of_change   = sy-uzeit
    tcode            = sy-tcode
    username         = sy-uname
  EXCEPTIONS
    no_position_found = 1
    OTHERS            = 2.

IF sy-subrc = 0.
  " Actually change data
  UPDATE zorder FROM ls_order_new.
  COMMIT WORK.
ENDIF.

Generated Function Module

" After SCDO definition, FM is generated: ZORDER_WRITE_DOCUMENT

DATA: ls_order_old TYPE zorder,
      ls_order_new TYPE zorder,
      lt_xorder    TYPE TABLE OF zorder,
      lt_yorder    TYPE TABLE OF zorder.

" Single record change
CALL FUNCTION 'ZORDER_WRITE_DOCUMENT'
  EXPORTING
    objectid         = ls_order_new-order_id
    tcode            = sy-tcode
    utime            = sy-uzeit
    udate            = sy-datum
    username         = sy-uname
    upd_zorder       = 'U'    " Update
  TABLES
    xzorder          = lt_xorder   " New data
    yzorder          = lt_yorder   " Old data
  EXCEPTIONS
    OTHERS           = 1.

Changes for Insert (Creation)

DATA: ls_order_new TYPE zorder.

" Create new order
ls_order_new-order_id    = '1000000002'.
ls_order_new-customer_id = 'CUST001'.
ls_order_new-status      = 'O'.
ls_order_new-amount      = 1000.

" Empty old record signals insert
DATA(ls_order_old) = VALUE zorder( ).

CALL FUNCTION 'CHANGEDOCUMENT_OPEN'
  EXPORTING
    objectclass = 'ZORDER'
    objectid    = ls_order_new-order_id.

CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
  EXPORTING
    tablename        = 'ZORDER'
    workarea_old     = ls_order_old
    workarea_new     = ls_order_new
    change_indicator = 'I'.  " Insert

CALL FUNCTION 'CHANGEDOCUMENT_CLOSE'
  EXPORTING
    objectclass    = 'ZORDER'
    objectid       = ls_order_new-order_id
    date_of_change = sy-datum
    time_of_change = sy-uzeit
    tcode          = sy-tcode
    username       = sy-uname.

INSERT zorder FROM ls_order_new.
COMMIT WORK.

Changes for Delete (Deletion)

DATA: ls_order_old TYPE zorder.

SELECT SINGLE * FROM zorder INTO ls_order_old
  WHERE order_id = '1000000001'.

" Empty new record signals delete
DATA(ls_order_new) = VALUE zorder( ).

CALL FUNCTION 'CHANGEDOCUMENT_OPEN'
  EXPORTING
    objectclass = 'ZORDER'
    objectid    = ls_order_old-order_id.

CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
  EXPORTING
    tablename        = 'ZORDER'
    workarea_old     = ls_order_old
    workarea_new     = ls_order_new
    change_indicator = 'D'.  " Delete

CALL FUNCTION 'CHANGEDOCUMENT_CLOSE'
  EXPORTING
    objectclass    = 'ZORDER'
    objectid       = ls_order_old-order_id
    date_of_change = sy-datum
    time_of_change = sy-uzeit
    tcode          = sy-tcode
    username       = sy-uname.

DELETE FROM zorder WHERE order_id = ls_order_old-order_id.
COMMIT WORK.

Log Multiple Tables

DATA: ls_header_old TYPE zorder_head,
      ls_header_new TYPE zorder_head,
      lt_items_old  TYPE TABLE OF zorder_item,
      lt_items_new  TYPE TABLE OF zorder_item.

" Open change document
CALL FUNCTION 'CHANGEDOCUMENT_OPEN'
  EXPORTING
    objectclass = 'ZORDER'
    objectid    = ls_header_new-order_id.

" Log header data
CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
  EXPORTING
    tablename        = 'ZORDER_HEAD'
    workarea_old     = ls_header_old
    workarea_new     = ls_header_new
    change_indicator = 'U'.

" Log items
LOOP AT lt_items_new INTO DATA(ls_item_new).
  READ TABLE lt_items_old INTO DATA(ls_item_old)
    WITH KEY item_id = ls_item_new-item_id.

  IF sy-subrc = 0.
    " Item changed
    CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
      EXPORTING
        tablename        = 'ZORDER_ITEM'
        workarea_old     = ls_item_old
        workarea_new     = ls_item_new
        change_indicator = 'U'.
  ELSE.
    " New item
    CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
      EXPORTING
        tablename        = 'ZORDER_ITEM'
        workarea_old     = VALUE zorder_item( )
        workarea_new     = ls_item_new
        change_indicator = 'I'.
  ENDIF.
ENDLOOP.

" Deleted items
LOOP AT lt_items_old INTO ls_item_old.
  READ TABLE lt_items_new TRANSPORTING NO FIELDS
    WITH KEY item_id = ls_item_old-item_id.

  IF sy-subrc <> 0.
    CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
      EXPORTING
        tablename        = 'ZORDER_ITEM'
        workarea_old     = ls_item_old
        workarea_new     = VALUE zorder_item( )
        change_indicator = 'D'.
  ENDIF.
ENDLOOP.

CALL FUNCTION 'CHANGEDOCUMENT_CLOSE'
  EXPORTING
    objectclass    = 'ZORDER'
    objectid       = ls_header_new-order_id
    date_of_change = sy-datum
    time_of_change = sy-uzeit
    tcode          = sy-tcode
    username       = sy-uname.

Read Change Documents

DATA: lt_cdhdr TYPE TABLE OF cdhdr,
      lt_cdpos TYPE TABLE OF cdpos.

" Read header data
SELECT * FROM cdhdr INTO TABLE lt_cdhdr
  WHERE objectclas = 'ZORDER'
    AND objectid   = '1000000001'
  ORDER BY udate DESCENDING, utime DESCENDING.

" Read item data
IF lt_cdhdr IS NOT INITIAL.
  SELECT * FROM cdpos INTO TABLE lt_cdpos
    FOR ALL ENTRIES IN lt_cdhdr
    WHERE objectclas = lt_cdhdr-objectclas
      AND objectid   = lt_cdhdr-objectid
      AND changenr   = lt_cdhdr-changenr.
ENDIF.

" Output
LOOP AT lt_cdhdr INTO DATA(ls_cdhdr).
  WRITE: / 'Changed on:', ls_cdhdr-udate, ls_cdhdr-utime,
           'by:', ls_cdhdr-username.

  LOOP AT lt_cdpos INTO DATA(ls_cdpos)
    WHERE changenr = ls_cdhdr-changenr.
    WRITE: / '  Field:', ls_cdpos-fname,
             'Old:', ls_cdpos-value_old(20),
             'New:', ls_cdpos-value_new(20).
  ENDLOOP.
ENDLOOP.

Change Documents with Class

CLASS zcl_change_document DEFINITION.
  PUBLIC SECTION.
    METHODS log_change
      IMPORTING
        iv_objectid  TYPE cdhdr-objectid
        is_old       TYPE any
        is_new       TYPE any
        iv_tablename TYPE tabname
        iv_operation TYPE cdchngind.  " I/U/D
ENDCLASS.

CLASS zcl_change_document IMPLEMENTATION.
  METHOD log_change.
    CALL FUNCTION 'CHANGEDOCUMENT_OPEN'
      EXPORTING
        objectclass = 'ZORDER'
        objectid    = iv_objectid.

    CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
      EXPORTING
        tablename        = iv_tablename
        workarea_old     = is_old
        workarea_new     = is_new
        change_indicator = iv_operation.

    CALL FUNCTION 'CHANGEDOCUMENT_CLOSE'
      EXPORTING
        objectclass    = 'ZORDER'
        objectid       = iv_objectid
        date_of_change = sy-datum
        time_of_change = sy-uzeit
        tcode          = sy-tcode
        username       = sy-uname
      EXCEPTIONS
        no_position_found = 1
        OTHERS            = 2.
  ENDMETHOD.
ENDCLASS.

Display Change Documents via ALV

DATA: lt_display TYPE TABLE OF ty_change_display.

SELECT h~objectid, h~udate, h~utime, h~username, h~tcode,
       p~tabname, p~fname, p~chngind,
       p~value_old, p~value_new
  FROM cdhdr AS h
  INNER JOIN cdpos AS p ON h~objectclas = p~objectclas
                       AND h~objectid   = p~objectid
                       AND h~changenr   = p~changenr
  WHERE h~objectclas = 'ZORDER'
    AND h~udate BETWEEN @lv_from_date AND @lv_to_date
  INTO CORRESPONDING FIELDS OF TABLE @lt_display
  ORDER BY h~udate DESCENDING, h~utime DESCENDING.

" Display ALV
cl_salv_table=>factory(
  IMPORTING r_salv_table = DATA(lo_alv)
  CHANGING  t_table      = lt_display ).

lo_alv->display( ).

Log Text Changes

" For long texts (e.g., notes)
DATA: lv_text_old TYPE string VALUE 'Old text',
      lv_text_new TYPE string VALUE 'New longer text'.

CALL FUNCTION 'CHANGEDOCUMENT_OPEN'
  EXPORTING
    objectclass = 'ZORDER'
    objectid    = lv_objectid.

" Log text change
CALL FUNCTION 'CHANGEDOCUMENT_TEXT_CASE'
  EXPORTING
    textcase        = 'X'
    text_old        = lv_text_old
    text_new        = lv_text_new
    tablename       = 'ZORDER'
    fieldname       = 'NOTES'
    change_indicator = 'U'.

CALL FUNCTION 'CHANGEDOCUMENT_CLOSE'
  EXPORTING
    objectclass    = 'ZORDER'
    objectid       = lv_objectid
    date_of_change = sy-datum
    time_of_change = sy-uzeit
    tcode          = sy-tcode
    username       = sy-uname.

Define Change Document Object in SCDO

1. Call transaction SCDO
2. Enter object name: ZORDER
3. Add tables:
   - ZORDER_HEAD (header table)
   - ZORDER_ITEM (item table)
4. Mark fields to be logged
5. Generate function module
6. Activate and transport

Batch Change Logging

" For mass changes
CALL FUNCTION 'CHANGEDOCUMENT_OPEN'
  EXPORTING
    objectclass = 'ZORDER'
    objectid    = '*MASS*'.  " Special ID

LOOP AT lt_changes INTO DATA(ls_change).
  CALL FUNCTION 'CHANGEDOCUMENT_SINGLE_CASE'
    EXPORTING
      tablename        = 'ZORDER'
      workarea_old     = ls_change-old_data
      workarea_new     = ls_change-new_data
      change_indicator = 'U'
      objectid         = ls_change-order_id.  " Per record
ENDLOOP.

CALL FUNCTION 'CHANGEDOCUMENT_CLOSE'
  EXPORTING
    objectclass    = 'ZORDER'
    objectid       = '*MASS*'
    date_of_change = sy-datum
    time_of_change = sy-uzeit
    tcode          = sy-tcode
    username       = sy-uname.

Change Indicators

Indicator	Description
I	Insert (creation)
U	Update (change)
D	Delete (deletion)
E	Single field change

CDPOS Structure

Field	Description
OBJECTCLAS	Change document object
OBJECTID	Object ID
CHANGENR	Change number
TABNAME	Table name
FNAME	Field name
CHNGIND	Change indicator
VALUE_OLD	Old value
VALUE_NEW	New value

Best Practices

Relevant fields: Only log business-relevant fields
Performance: Write change documents in update task
Object ID: Use unique, meaningful ID
Archiving: Archive old change documents (SARA)
Authorizations: Protect read access to change documents
Compliance: Consider retention period requirements

Application Logging - Application logging
Lock Objects - Lock management
Authorization Checks - Access control
BAPI Development - Document processing

ABAP Change Documents: Logging Data Changes

Change Document Concepts

Important Transactions

Basic Examples

Write Change Document

Generated Function Module

Changes for Insert (Creation)

Changes for Delete (Deletion)

Log Multiple Tables

Read Change Documents

Change Documents with Class

Display Change Documents via ALV

Log Text Changes

Define Change Document Object in SCDO

Batch Change Logging

Change Indicators

CDPOS Structure

Best Practices

Related Topics