MM User Exit : MB_CF001

Question

Can anyone please tell me when do this user exit break.

Answer 1

The enhancement MB_CF001 includes a function module that is called up immediately before the COMMIT WORK when a goods movement is posted.                                                                               
All the material document data is passed on to this function module from the following tables:                                                   
o  MKPF     (Material document header)                                  
o  MSEG     (Material document items)                                   
o  VM07M    (Update data)                                                                               
This data can be passed on to other programs.                                                                               
Note                                                                               
The enhancement does not write any data to the material document, that is, it is not possible to change material document data before the update posting takes place.                                                                               
If the enhancement MB_CF001 (component: Function module EXIT_SAPLMBMB_001with Include ZXMBCU01) is implemented incorrectly, an inconsistency may occur between documents and stocks as well as between material documents  and accounting documents. Such inconsistencies can be caused by the following elements in the user exit, for example:                        
o  COMMIT WORK                                                           
o  Remote function call (CALL FUNCTION .. DESTINATION)                   
o  Separate updates on the document or stock tables (for example, an     
    update on table MBEW, MARD, MSEG)                                     
o  Unlocking data (for example, through DEQUEUE_ALL)                                                                               
The enhancement MB_CF001 is called in the update function module  MB_POST_DOCUMENT. If a COMMIT WORK or a Remote Function Call is set in the enhancement, a complete ROLL BACK is not possible in the case of an update termination, since data has already been written until the COMMIT 
or the remote function call in the database. Consequently, an asynchronous status (for example, a material document without accounting document), which can only be repaired with considerable effort, may be the result.                                                                               
The enhancement MB_CF001 is not suited for customer-specific updates on the stock tables, because such updates can destroy the standard inventory update if they are not programmed incrementally (see Note 6899), or if  they do not take the material blocks into account.          
Unlocking data (for example, using DEQUEUE_ALL) is also very important, as the data to be updated is no longer protected against external updates, and inconsistencies can result from parallel updates.                                                                               
Before you activate an enhancement, check thoroughly that the user exit does not contain high priority source code positions.                                                                               
If data inconsistencies have already occurred in your system, inconsistencies that can be traced back to the user exits, remove the high priority source code positions immediately before they cause further
inconsistencies.