Fetch ECC table data into BW using RFC function Module

Business Requirement:

In ECC some mapping tables are available.

Copy those table data into BW.

Implementation Logic in BW

This can be achieved in 2 ways:

1. 1. create table based extractor in ECC and load data into BW.
2. 2. Copy table data dirctly from ECC to BW using RFC function Module ‘RFC_GET_TABLE_ENTRIES’.

I tried to explain second approch here.

Logic

   CALL FUNCTION ‘RFC_GET_TABLE_ENTRIES’ DESTINATION  destination   ****** destination is RFC destination/ system from which data to be fetched

EXPORTING
*       BYPASS_BUFFER           = ‘ ‘
*       FROM_KEY                        = ‘ ‘
*       GEN_KEY                           = ‘ ‘
*       MAX_ENTRIES                  = 0
         table_name                         = table_name  ****** Name of table of which we want to fetch the data
*       TO_KEY                               = ‘ ‘
*     IMPORTING
*       NUMBER_OF_ENTRIES   =
    TABLES
      entries                                    = lt_tab1
   EXCEPTIONS
     internal_error                           = 1
     table_empty                             = 2
     table_not_found                      = 3
     OTHERS                                  = 4
            .
  IF sy-subrc <> 0.
    CASE sy-subrc.

      WHEN 1.
        MESSAGE e001.
        RAISE internal_error.
      WHEN 2.
        MESSAGE e002.
        RAISE table_empty.
      WHEN 3.
        MESSAGE e003.
        RAISE table_not_found.
      WHEN OTHERS.
        MESSAGE e004.
        RAISE others.
    ENDCASE.
  ENDIF.
**** data returned in FM is in string format, we need to create table structure dynamically and then use that data

* create field structure

  CALL FUNCTION ‘LVC_FIELDCATALOG_MERGE’
    EXPORTING
*     I_BUFFER_ACTIVE                =
      i_structure_name                    = table_name
*     I_CLIENT_NEVER_DISPLAY = ‘X’
*     I_BYPASSING_BUFFER        =
*     i_internal_tabname                 =
    CHANGING
      ct_fieldcat                                = lt_fcat
    EXCEPTIONS
      inconsistent_interface = 1
      program_error             = 2
      OTHERS                     = 3.
  IF sy-subrc <> 0.
    CASE sy-subrc.
      WHEN 1.
        MESSAGE e005.
      WHEN 2.
        MESSAGE e006.
      WHEN OTHERS.
        MESSAGE e007.
    ENDCASE.
  ENDIF.

* Generate Dynamic table for field catalog
  CALL METHOD cl_alv_table_create=>create_dynamic_table
    EXPORTING
      it_fieldcatalog = lt_fcat
    IMPORTING
      ep_table        = lt_dyn_table.

  ASSIGN lt_dyn_table->* TO <l_dyn_table>.
  CREATE DATA ls_dyn_struct LIKE LINE OF <l_dyn_table>.
  ASSIGN ls_dyn_struct->* TO <l_dyn_struct>.

  LOOP AT lt_tab1 INTO wa_tab1.
    <l_dyn_struct> = wa_tab1.
    APPEND <l_dyn_struct> TO <l_dyn_table>.
  ENDLOOP.

  MODIFY table_name FROM TABLE <l_dyn_table>.
  IF sy-subrc = 0.
    l_success = 1.
  ENDIF.

Advantages of this approach:

1. 1. We can store data in transparent table (se11 z table).
2. 2. IF data volume is fixed and small it takes less time than normal extraction process

Disadvantages of this approach:

1. 1. If data volume is high and increasing over period of time, internal table memory errors may occur.