Function Module Call Via CMOD Logic for Master Data Enhancement

Question

Hi Friends Please help me to resolve this, would really be very kind of all of you.
Requirement. I want to Enhance the field ZFACTREG from VIBDBE table in my datasource 0busentity_attr extract structure l_s_REIS_BUSENTITY_ATTR, I want to create the logic in CMOD exit_saplrsap_002 to call my function module for enhancement of master data. Please help me Step by Step
Thanks
Poonam Roy
<b>Step #1</b>
I put this code which gives me error in CMOD like this
ERROR : Das formale Argument 'OTHERS' muss am Schluss der Ausnahmeliste stehen.
ABAP Code#1 IN exit_saplrsap_002     
DATA: l_d_fmname(30) TYPE c.
CONCATENATE 'Z_DS_' i_datasource(25) INTO l_d_fmname.
TRY.
CALL FUNCTION l_d_fmname
EXPORTING
I_DATASOURCE = I_DATASOURCE
I_UPDMODE = I_UPDMODE
TABLES
I_T_SELECT = I_T_SELECT
I_T_FIELDS = I_T_FIELDS
I_T_DATA = I_T_DATA
C_T_MESSAGES = C_T_MESSAGES
EXCEPTIONS
RSAP_CUSTOMER_EXIT_ERROR = 1
OTHERS = 2
IF FOUND.
IF SY-SUBRC <> 0.
RASIE RSAP_CUSTOMER_EXIT_ERROR.
END IF
CATCH CX_SY_DYN_CALL_ILLEGAL_FUNC.
ENDTRY.
<b>Step#2</b>
I simple created the Function module Z_DS_BUSINESS
and put the code in source code  which gives me error . what should i put in other tabs like"Import", Export", Tables" i kept blank
ABAP CODE give me error : The Dictionary structure or table "FIELD-SYMBOLS" is either not active. i have to remove include in the FM. WHY SO??
FUNCTION Z_DS_BUSINENSS
""Lokale Schnittstelle:
*"       IMPORTING
*"             VALUE(I_DATASOURCE) TYPE  RSAOT_OLTPSOURCE
*"             VALUE(I_CHABASNM) TYPE  SBIWA_S_INTERFACE-CHABASNM
*"             VALUE(I_UPDMODE) TYPE  SBIWA_S_INTERFACE-UPDMODE
*"       TABLES
*"              I_T_SELECT TYPE  SBIWA_T_SELECT
*"              I_T_FIELDS TYPE  SBIWA_T_FIELDS
*"              I_T_DATA
*"              C_T_MESSAGES STRUCTURE  BALMI OPTIONAL
*"       EXCEPTIONS
*"              RSAP_CUSTOMER_EXIT_ERROR
INCLUDE ZXRSAU02.
  WRITE: / 'INSIDE THE Z_DS_MEASUREMENTS PROGRAM'.
TABLES: REIS_BUSENTITY_ATTR,
        VIBDBE,
field-symbols:.<fs_REIS_BUSENTITY_ATTR> like REIS_BUSENTITY_ATTR.
DATA: BEGIN OF i_c_t_data OCCURS 0.
          include structure REIS_BUSENTITY_ATTR.
DATA END OF i_c_t_data.
DATA: i_c_t_data_copy like i_c_t_data OCCURS 0 WITH HEADER LINE,
      begin of i_vibdbe occurs 0,
      INTRENO like vibdbe-INTRENO,
      ZFACTREG like vibdbe-ZFACTREG,
              end of i_vibdbe.
i_c_t_data_copy[] = i_c_t_data[] = c_t_data[].
sort i_c_t_data_copy by vibdbe.
Select  INTRENO
        into table i_VIBDBE from VIBDBE
        for all entries in i_c_t_data_copy
        where  INTRENO = i_c_t_data_copy- INTRENO.
if sy-subrc = 0.
  sort i_VIBDBE by INTRENO.
  loop at i_c_t_data assigning <fs_REIS_BUSENTITY_ATTR>.
    clear: i_VIBDBE.
    read table i_VIBDBE with key INTRENO = <fs_REIS_BUSENTITY_ATTR>-INTRENO
    BINARY SEARCH
    transporting ZFACTREG .
    if sy-subrc = 0.
      <fs_REIS_BUSENTITY_ATTR>-ZZFACTORY = i_vibebe-ZFACTREG
    endif.
null

Answer 1

(I leave office until Monday morning, Europe time)
in include from customer-exit ZXRSAU01, etc.
CASE I_DATASOURCE.
WHEN '0CUSTOMER_ATTR'.
   PERFORM 0customer_attr changing i_t_data...
ENDCASE.
In each perform, doing what you wrote ; select (needed fields) from complementary-database-table into an internal table with a for all entries. sort the table. LOOP and MODIFY on i_t_data.
In some case i had to insert lines of i_t_data to an internal table of DS_structure when entering subroutine and back at exit. (on 4.6C PI 2003 if i remember)
Some optimization done when reading small tables (T001 society and the same, these are filled once and not for each packet of data.
Your idea of creating different FM is of interest, but the cost of passing i_t_data between two programs (two function groups) may overcome the gain of performance. In a job only one DataSource is processed so only one routine is actually called.
Regards.