Are you talking about standard auditing or fine grained auditing ?

For the former, you can choose what you want. From the docs:


WHENEVER [NOT] SUCCESSFUL

Specify WHENEVER SUCCESSFUL to audit only SQL statements and operations that succeed.

Specify WHENEVER NOT SUCCESSFUL to audit only statements and operations that fail or result in errors.

If you omit this clause, then Oracle Database performs the audit regardless of success or failure.


For the latter, we only log when the fga condition is triggered

SQL> grant dba to demo identified by demo;

Grant succeeded.

SQL>
SQL> connect demo/demo
Connected.

SQL> create table emp as select * from scott.emp;

Table created.

SQL> begin
  2              dbms_fga.add_policy
  3              ( object_schema   => user,
  4                object_name     => 'EMP',
  5                policy_name     => 'ENAME_SAL',
  6                audit_condition => 'sal > 1500',
  7                audit_column    => 'SAL' );
  8  end;
  9  /

PL/SQL procedure successfully completed.

SQL>
SQL> exec dbms_stats.gather_table_stats('','EMP');

PL/SQL procedure successfully completed.

SQL>
SQL> select empno, ename from emp;

     EMPNO ENAME
---------- ----------
      7369 SMITH
      7499 ALLEN
      7521 WARD
      7566 JONES
      7654 MARTIN
      7698 BLAKE
      7782 CLARK
      7788 SCOTT
      7839 KING
      7844 TURNER
      7876 ADAMS
      7900 JAMES
      7902 FORD
      7934 MILLER

14 rows selected.

SQL>
SQL> select * from dba_fga_audit_trail;

no rows selected

SQL>
SQL> variable sal number
SQL> execute :sal := 1400

PL/SQL procedure successfully completed.

SQL>
SQL> select empno, ename from emp where sal < :sal;

     EMPNO ENAME
---------- ----------
      7369 SMITH
      7521 WARD
      7654 MARTIN
      7876 ADAMS
      7900 JAMES
      7934 MILLER

6 rows selected.

SQL> execute :sal := 1700

PL/SQL procedure successfully completed.

SQL>
SQL> select empno, ename from emp where sal < :sal;

     EMPNO ENAME
---------- ----------
      7369 SMITH
      7499 ALLEN
      7521 WARD
      7654 MARTIN
      7844 TURNER
      7876 ADAMS
      7900 JAMES
      7934 MILLER

8 rows selected.

SQL>
SQL> @pt "select * from dba_fga_audit_trail"
old   2: p_query varchar2(32767) := q'{&1}';
new   2: p_query varchar2(32767) := q'{select * from dba_fga_audit_trail}';
SESSION_ID                    : 680517
TIMESTAMP                     : 19-jan-2016 09:15:21
DB_USER                       : DEMO
OS_USER                       : comcdona
USERHOST                      : ORADEV\COMCDONA-AU
CLIENT_ID                     :
ECONTEXT_ID                   :
EXT_NAME                      :
OBJECT_SCHEMA                 : DEMO
OBJECT_NAME                   : EMP
POLICY_NAME                   : ENAME_SAL
SCN                           : 7990715
SQL_TEXT                      : select empno, ename from emp where sal < :sal
SQL_BIND                      :  #1(4):1700
COMMENT$TEXT                  :
STATEMENT_TYPE                : SELECT
EXTENDED_TIMESTAMP            : 19-JAN-16 09.15.21.512000 AM +08:00
PROXY_SESSIONID               :
GLOBAL_UID                    :
INSTANCE_NUMBER               : 0
OS_PROCESS                    : 4132:4340
TRANSACTIONID                 :
STATEMENTID                   : 50
ENTRYID                       : 2
OBJ_EDITION_NAME              :
DBID                          : 1914458800
-----------------

PL/SQL procedure successfully completed.

SQL>
SQL>