ORA_PRIVILEGE_LIST returns the number of elements in the list indexed by a PLS_INTEGER datatype.
SQL> SQL> SQL> DECLARE 2 priv_list DBMS_STANDARD.ORA_NAME_LIST_T; 3 counter PLS_INTEGER; 4 BEGIN 5 IF ora_sysevent = 'GRANT' OR ora_sysevent = 'REVOKE' THEN 6 counter := ora_privilege_list(priv_list); 7 dbms_output.put_line('counter:'||counter); 8 END IF; 9 END; 10 / PL/SQL procedure successfully completed. SQL> SQL>