ABAP, NetWeaver, ERP Tutorial

The purpose of a reservation is to ensure that a material will be available when it is needed. It also serves to simplify and accelerate the goods issue process and prepare the tasks at the point of goods issue.It is also important that reservations are taken into account by Material Requirements Planning (MRP), which means that required materials are procured in time if they are out of stock.

Reservation can be created manually or it can be created by MRP logic. The field [RESB-RSSTA] indicate whether the reservation is created manually or automatically.

We can reate a new reservation using tcode MB21. After the reservation is created, we can see this reservation has been taken as an MRP element. Enter the tcode MD04:

We can also perform an ATP against the reservation items. Go to Edit -> Additional Functions -> Check Availabilities. System will check how many quantities are available at request time. After save the reservation, the reservation will update confirmed quantity according to availability check. The confirm quantity will taken into consideration during further ATP check. Go to Tcode CO09, you will find the confirmed quantity for the reservation.

We can also use the BAPI to change the reservation w/o ATP check. It is very useful, if business wants to have a group ATP check according to selected reservations. For this requirement, we need write a custom report and use below code to update reservation with ATP check.

DATA: lt_reserv_c  TYPE TABLE OF bapi2093_res_item_change,
       lt_reserv_cx TYPE TABLE OF bapi2093_res_item_changex,
       lt_return    TYPE TABLE OF bapiret2,
       ls_reserv_c  TYPE bapi2093_res_item_change,
       ls_reserv_cx TYPE bapi2093_res_item_changex,
       ls_check     TYPE bapi2093_atpcheck,
       ls_no_check  TYPE bapi2093_atpcheck.
 
    ls_check-atpcheck = 'X'.
    ls_no_check-atpcheck = ' '.
 
*...fill reservation change table
 
     CALL FUNCTION 'BAPI_RESERVATION_CHANGE'
      EXPORTING
        reservation                     = lv_rsnum
        atpcheck                        = ls_check " do ATP check at first time
      TABLES
        reservationitems_changed        = lt_reserv_c
        reservationitems_changedx       = lt_reserv_cx
        return                          = lt_return.
 
    COMMIT WORK AND WAIT.

Additional information:

Reservation related table:
RKPF -Document Header: Reservation
RESB -Reservation/dependent requirements

Related Tcode:
MB26 -Picking list