Creation of Change Documents 
In transaction S_AUT01, you activate logging for an individual data element. This logging is based on the creation of change documents.
Note
In general, no change documents are stored when data is created. The original data records are visible via the associated change or display transaction. It is thus unnecessary to record the creation of a data record redundantly as a log. Only if the original values are changed is it necessary to store logs relating to GMP-relevant data.
Prerequisites
The following prerequisites must be satisfied for the change document creation process to function correctly:
The data element to be logged must be included in a table that is assigned to a change document object. You can see the assignment in the transaction S_AUT01.
This change document object must be implemented in the application that is to be logged. In this implementation, the necessary old and new values must be transferred from the application to the change document creation facility.
For some applications, such as work center or functional location, the following additionally applies:
The change document creation facility must be activated in Customizing or it functions only in dependence on certain settings.
Features
If the prerequisites under point 1 or point 2 are not satisfied, you cannot use the change document object implemented by SAP. In this case, you can only log the changes by using the table logging functionality.
You can implement a change document object of your own or an already-existing one in an existing user exit or a BAdI. In this case, the generated function module must be invoked for change document creation and the fields of the changed table must additionally be populated correctly. See also: Creation of Events When Change Documents Are Written
Note
If no logs are created even though all prerequisites have been satisfied, it may be that inactive versions exist. You can get rid of these (see : Remove Inactive Versions)
Constraints
Audit Trail does not include the enhancement of existing change document objects.
Audit Trail does not include new change document objects.
Audit Trail does not implement change document objects in applications.
Changes in status objects (tables JSTO and JEST) cannot be displayed using transaction S_AUT10. To do this, use the application-specific evaluation function.