Userxits allow us to add our own functionality to SAP standard program
without modifying it . These are implemented in the form of subroutines and hence are also known as FORM EXITs.
The userexits are generally collected in includes and attached to the standard program by the SAP.
All Userexits start with the word USEREXIT_...
The problem lies in finding the correct userexit and how to find it if one exists for the purpose. Once the correct userexit
is found the necessary
customer code is inserted in the customer include starting with the z..
in the form routine.
Certain application like SD still provide this form of enhancement using userexit but this practice is no longer being
followed for newer extensions
instead they are using EXITs which come bundeled in enhancement packages . Neverthiless existing USEREXITS will be supported
by SAP an all the newer versions of SAP.
HOW TO FIND USEREXITS
Userexits can be found in number of ways:
1) To find userexits in SD module , goto object navigator(SE80) and select
development class from the list and enter VMOD in it. All of the userexits in SD are contained in
the development class VMOD. Press
enter and you will find all the includes which contain userexits in SD for
different functions like PRICING, ORDER PROCESSING etc. Select the userexit according to the requirement and read the
comment inserted in it
and start coding .
Some examples of userexits in SD(SALES & DISTRIBUTION ) are:
1)ADDING OF NEW FIELDS IN PRICING
In Pricing in SD the fields on the basis of which pricing is done are derived from the FIELD CATALOG which is a
structure KOMG .This structure is used to transfer transaction data to the pricing procedure in SD and is also known as communication
structure.This structure KOMG consists of two tables KOMK for Header related fields and KOMP for item related fields.
The fields which are not in either of the two tables KOMK and KOMP
cannot be used in pricing .Sometimes a need arises when the pricing
is to be based on some other criteria which is not present in the form of fields in either of the two tables.
This problem can be solved by using USEREXITS which are provided for pricing in SD.
Pricing takes place both when the SALES ORDER ( Transaction VA01) is created as well as when INVOICING (
Transaction VF01) is done.Hence SAP provides 2 userexits ,one for sales order processing which is
Depending upon which table (KOMK or KOMP) the new fields were inserted we use either of the above two userexits.These
userexits are found in include MV45AFZZ of the standard SAP sales order creation program SAPMV45A.
In the case of userexit which will be called when invoicing is done ,these
are provided in the include RY60AFZZ which is in the standard SAP
program SAPMV45A. The name of the userexits are same. i.e
These userexits are used for passing the data from the communication structure to the pricing procedure, for this we
have to fill the newely
created field in the communication structure KOMG for this we fill the code in the above userexit using the MOVE statement
after the data that
has to be passed is taken from the database table by using the SELECT statement. The actual structure which is visible
in these userexits and which is to be filled for that particular field is TKOMP or TKOMK.
Before the coding for these userexits is done ,it is necessary to create a new field in either of the two tables KOMK
or KOMP .For this purpose
includes are provided in each of them .
To create the field in header data(KOMK) the include provided is KOMKAZ
and to create the field in item data(KOMP) the include provided is KOMPAZ.
One possible example for the need of creating new fields can be e.g. Frieght to be based upon transportation zone ,for
this no field is available in field catalog and hence it can be created in KOMK and then above userexits can be used to fill
the transportation data to it.
2)The other method of finding userexit is to find the word USEREXIT in the
associated program of the transaction for which we want to determine userexit using SE38.