Creation of Events When Change Documents are Written 
Event creation can be connected to the writing of a change document without modifying an existing application.
Many business objects are changed frequently. It is often useful, and even necessary, to be able to trace the changes made. This logging is carried out with change documents. These can be created for changes already made as well as for planned changes.
To be able to log changes to a business object in a change document, an appropriate change document object must be defined in the system. In its definition, a change document object has tables, which represent a business object in the system. Changes to table fields designated as change document-relevant are logged by writing a change document.
Example
Changes made to the material master data in the field MARA-WRKST (basic material) are logged as standard on the part of the application in a change document for the change document object MATERIAL.
For more information about change documents, see the documentation Change Documents.
The assignment between a change document object and a business object type/event must be maintained in a system table. The system then creates the event whenever a change document is written for the change document object. The change document is written when the change is updated. The procedure described, putting the event after the logging, ensures that the event is not created until the change has actually been made.
The system fills the event container of the event created with information about the change document. For more information and advice on how to use these event parameters, see Creation of Additional Event Parameters with Event Creation.
Assign a change document object to an object type/event pairing and determine the action (create, change or delete) on the application object for which the event is to be created. You can classify the event in order to create three different events for a change document, if appropriate from a business point of view.
For more information, see Maintaining the Assignment Between Change Document and Event Without Field Restrictions.
You may restrict the event creation with regard to whether the change document or change meets certain conditions.
For more information, see Maintaining the Assignment Between Change Document and Event with Field Restrictions.
You may specify a function module with which you can still perform operations on the event container immediately before the event manager is called, that is, before possible event receivers are determined.
This function module is only required under specific circumstances.