track user changes in customized table

from:http://www.sapfans.com/forums/viewtopic.php?f=13&t=329229

One method is table logging.
Within 'Technical Settings' for a table, there is an option for 'Log data changes'
If this is selected AND table logging is active within the system, you can evaluate the changes via transaction SCU3.
SAP supply a number of tables with this setting switched on.

Another standard method is utilising 'Change Documents' which are set at Data Element level within tables.

from: http://naidukyalla.blogspot.com/2010/07/sap-table-logging.html

Table logging is a functionality SAP provides to automatically track changes on tables set as "LOG DATA CHANGES".
By default SAP delivers mainly config tables set like that since the main reason was to enable automatic logging of config changes.
The functionality could indeed harm your system performance but , as per OSS note 608835, you should not have problems since only config tables are set to be logged...
"Generally, you can activate logging in your system without any problems because SAP only delivers Customizing tables with activated logging. Customizing tables usually contain a relatively small amount of data which is only changed occasionally.
To be more precise: Basically all Customizing tables are delivered with activated logging because the requirements of external auditors are inconsistent as regards the logging of tables.
Tables for master and transaction data, on the other hand, are delivered by SAP without logging indicators. A large number of these tables are subject to mass changes which would cause performance problems if they were logged. You should use great caution if you want to log any of these tables.
Practice has shown that, bearing the above restrictions in mind, logging does not cause any problems in the production, Customizing and development environments.
If performance or memory problems occur unexpectedly, you can easily determine which table causes the problems:
Select the "Administration --> Number of logs (selective)" menu option (Shift+F8) in transaction scu3. Enter a time interval in the selection screen displayed and leave the table selection empty. If you now start the report, it returns a list of all logged tables with the number of recorded logs. You can then deactivate the logging of the tables most frequently logged in transaction SE13.
As described above, SAP delivers all Customizing tables with activated logging. Due to the relatively low number of changes in Customizing, it is not useful to remove the logging indicator from all tables except a selected few, especially since the requirements for the logging of pages may be changed by your external auditor from time to time."

If you want to monitor changes in application tables, you need to rely on aplication change objects. Ex: for table MARA, we don't have it set to auto changes, yet, we have the log of changes through standard change objects, programmed within the standard MM02, MM01... transactions.