Understanding Different Types of SAP Function Modules: Normal, RFC, and Update

 

1. Normal/Regular Function Module :-

• It can be called inside the system.
• Here Pass by value + Pass by reference both is fine.

2. RFC Function Modules :-

• You can call from same system or from another possible.

• In RFC function module you can only have pass by value.

• In the same system if you are going to add the DESTINATION

  NONE’ while calling the RFC then it’ll be called in separate session.

3. UPDATE Function Modules :-

• This is generally used to update the database record.
• Update Function Module can be called from the same system. ( Background RFC / trfc / grfc )
• This is used to achieve generally the SAP LUW.
• Some time we use from performance perspective also.
• When COMMIT WORK gets executed then Update starts getting executed.

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Important Questions on Update Function Modules :-

1. When Update function Module gets Triggered ?

• ON COMMIT WORK

1. IF a update function module gets failed, under which transaction we can see that ?

   OR

   What is the T-Code for monitoring the Update function module failures ?

• SM13

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let’s create a remote Function Module.

Requirement :-

• Suppose, we have a vendor portal which is extended to SAP.
• So, the requirement is when Vendor Login to the Portal, We have to show him the list of Purchase Order though RFC.

Solution :-

Part 1 :- Creating function Module

• Step 1 :- Go to SE37.

• Step 2 :- Give name and function group.

  
  
  

  
  

• Step 3 :- Open the attributes tab and select remote enabled module.

  
  
  

  
  

• Step 4 :- Take import parameters.

  
  
  

  
  

• Step 5:- Give a export parameter to display the message in export section.

  
  
  
  
  
  
  

  
  

• Step 6 :- define parameters in tables section.

  
  
  

  
  

• Step 7 :- Write the logic in source code.

  
  
  

  
  

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  Part 2 :- Creating RFC Destination

• Step 1 :- go to SM59 and click on ABAP connections.

  
  
  

  
  

• Step 2 :- Click on create button.

• Step 3 :- Provide the destination → connection type → description → target host → instance number.

  
  
  

  
  

• Press enter.

• Step 4 :- Click on Login and security.

• Step 5 :- In the login and security → provide language → client number → user → password → click on save.

  
  
  

  
  

• Step 6 :- Click on Connection test.

  
  
  

  
  

  • As you can see connection was successful.

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Part 3 :- Calling RFC in the program.

• Step 1 :- Go to ABAP editor and create a executable program.

• Step 2 :- Follow the below program.

  
  
  

  
  

  • We have used the destination of our RFC.

Code.

*****************************************************
*Start of Program
***********************

DATA : lt_ekko TYPE TABLE OF ekko,
       lt_ekpo TYPE TABLE OF ekpo,
       gv_msg  TYPE string.

PARAMETERS : p_lifnr TYPE lifnr,
             p_ebeln TYPE ebeln.

START-OF-SELECTION.

  CALL FUNCTION 'ZAR_VENDOR_PO' DESTINATION 'ZDRFC'
    EXPORTING
      ip_lifnr = p_lifnr
      ip_ebeln = p_ebeln
    IMPORTING
      ep_msg   = gv_msg
    TABLES
      ot_ekko  = lt_ekko
      ot_ekpo  = lt_ekpo.

  IF lt_ekko is not INITIAL.

    CL_DEMO_OUTPUT=>DISPLAY( lt_ekko ).

  ELSEIF lt_ekpo[] is not INITIAL.
    CL_DEMO_OUTPUT=>DISPLAY( lt_ekpo ).

  ELSE.
    WRITE : gv_msg.

  ENDIF.

**********************************
*End of Program
****************************************************

Execute the Program :-

• For lifnr first.

  
  
  

  
  

  • Press F8.

    
    
    

    
    

• For lifnr and ebeln both

  
  
  

  
  

  • Press F8.

    
    
    

    
    

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