1. Database activities are classified into three types: application activities, administration activities and database events.

2. Oracle triggers provide a way to create an audit trail for DDL changes and database activities.

3. Oracle database activities that can be tracked include user logon and logoff, as well as database startup and shutdown.

4. Oracle provides a way to audit activities, for example, who is creating or modifying the structure of a specific object and who granted which privileges to whom.

5. Oracle provides the AUDIT command, which is a SQL command for auditing.

6. The Oracle initialization parameter, AUDIT_TRAIL, specifies the destination of the audit trail file.

7. The Oracle NOAUDIT statement is used to stop auditing.

8. The Oracle DBA_AUDIT_TRAIL data dictionary view contains the audit trail data.

9. The Oracle Alert log is another method of auditing database activities.

10. Oracle Alert log contains information related to errors, such as database startup and shutdown events , modified initialization parameters,checkpoints,archiving ,and physical database charges.