Regarding ENQUEUE DEQUEUE

Question

hey guys,
I want to make record level lock for the user entered in the screen Simultaneously.
I have change button and Tablecontrol in screen.
when user enter VBELN and Other values and execute, the retrieved values from
internal table will be popupated in table control at next screen 9100.
I want to lock other user whom tries to make change in this screen or <b>(when he clicks change button in screen)</b>
i did below logic and its not working for me..could you pls help me out.
MAIN PROGRAM******************************************************
SELECT-OPTIONS:S_WADAT   FOR LIKP-WADAT_IST.       
SELECT-OPTIONS:S_KUNAG   FOR LIKP-KUNAG.          
SELECT-OPTIONS:S_KUNNR   FOR LIKP-KUNNR.           
SELECT-OPTIONS:S_LGORT   FOR LIPS-LGORT            
                         MATCHCODE OBJECT ZMLG.
SELECT-OPTIONS:S_VGBEL   FOR LIPS-VGBEL.          
SELECT-OPTIONS:S_VBELN   FOR LIKP-VBELN.        
SELECT-OPTIONS:S_POSNR   FOR LIPS-POSNR.           
SELECT-OPTIONS:S_ZBUNK   FOR ZSDTB_LOT-ZBUNKTU.  
<b>START-OF-SELECTION.</b>
  CLEAR:FLG_CHG,                                   
        FLG_UPD.                                 
  FLG_SAV = C_ON.                               
  <b>PERFORM SEL_DATA.</b> <i>"Fetches data and put into internal table IT_DATA.</i>
  CLEAR W_LINE.
  DESCRIBE TABLE IT_DATA LINES W_LINE.         
  IF W_LINE = 0.                                  
     MESSAGE ID 'ZPP' TYPE 'S' NUMBER '011'.
  ELSE.
   <b>  CALL SCREEN '9100'.   </b>
  ENDIF.
PERFORM DEQ_TBL.          
FORM SEL_DATA.
STORED VALUES INTERNAL TABLE IT_DATA.
ENDFORM.
*WHEN USER CLICK CHANGE BUTTON in APPLICATION BAR>
MODULE USER_COMMAND_9100 INPUT.
  CASE OK_CODE.                   
    WHEN 'CSCG'.           "Change button                         
     IF FLG_CHG = C_ON.
     CLEAR:FLG_CHG,FLG_SAV.
     LOOP AT IT_DATA INTO WA_DATA.
     AT END OF VBELN.
      <b> PERFORM ENQ_TBL USING WA_DATA.
       IF FLG_ERR = C_ON.
        EXIT.
        ENDIF.</b> 
    ENDAT.
     ENDLOOP.
    IF FLG_ERR = C_ON.
     <b>MESSAGE ....<.INFORMATION ERROR VBELN LOCKED></b>    ENDIF.
     IF FLG_UPD = C_ON.                       
        PERFORM INSERT_TBL.                  
     ENDIF.
    ELSE.
         FLG_CHG = C_ON.
    ENDIF.
    WHEN 'SAVE'.                    
      IF FLG_UPD = C_ON.                           
         PERFORM INSERT_TBL.                        
      ENDIF.
  ENDCASE.
ENDMODULE.          
<b>FORM ENQ_TBL  USING    I_VBELN.
  CLEAR FLG_ERR.
  CALL FUNCTION 'ENQUEUE_EZSDTB_LOT'
    EXPORTING
      MODE_ZSDTB_LOT       = 'E'
      MANDT                = SY-MANDT
      VBELN                = I_VBELN
    EXCEPTIONS
      FOREIGN_LOCK         = 1
      SYSTEM_FAILURE       = 2
      OTHERS               = 3
IF SY-SUBRC <> 0.
    FLG_ERR = C_ON.
ENDIF.</b>ENDFORM.                    " ENQ_TBL

Answer 1

hi, please descript more details on where the problem is.
Specially the symptom of your problem.
if you want to keep the exclusive access on thoes record, other application should also call 'ENQUEUE_EZSDTB_LOT' to try to get the access authority.
if no, your lock won't be effective.
And if the other application will be runned by a same user account in the SAP sever, you also should check the 'lock mode' of the lock object.
It is cumulative or not.
It's important, because Exclusive locks can be requested by the same transaction more than once and handled successively, but an exclusive but not cumulative lock can only be requested once by a given transaction. All other lock requests are rejected.
Hope it will be helpful
thanks