In SD Pricing , 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
USEREXIT_PRICING_PREPARE_TKOMP or
USEREXIT_PRICING_PREPARE_TKOMK
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.
USEREXIT_PRICING_PREPARE_TKOMP or
USEREXIT_PRICING_PREPARE_TKOMK
These userexits are used for passing the data from the communication structure to the pricing procedure, for this we have to fill the newly 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 .
One possible example for the need of creating new fields can be e.g. Freight 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.
