For any Oracle versions prior to 9i you will need to set audit_trail parameter in the pfile ie.g.:
audit_trail = DB
For later Oracle Versions:
SQL>alter system set audit_trail = DB;
To enable auditing for a specific object run the following command:
SQL>AUDIT SELECT, INSERT, UPDATE, DELETE ON SCHEMA.TABLE;
To stop auditing use:
SQL>NOAUDIT SELECT, INSERT, UPDATE, DELETE ON SCHEMA.TABLE;
Or to audit any statement that queries, delete, insert or updates any table, issue the following statement:
AUDIT SELECT TABLE, DELETE TABLE, INSERT TABLE, UPDATE TABLE;
If you want to audit a specific user will need to run the following commands:
AUDIT ALTER TABLE, SELECT TABLE, INSERT TABLE, ... ,GRANT PROCEDURE by <USERNAME>;
To stop the audit for the user you will need to run:
NOAUDIT ALTER TABLE, SELECT TABLE, INSERT TABLE, ... ,GRANT PROCEDURE by <USERNAME>;
To see the results of the auditing use please run:
SQL> select * from dba_audit_trail;
This is an excellent Oracle documentation to learn how to implement it:
Also I’ll recommend you to take a look on the following links:
Cheers,Francisco Munoz Alvarez