Connected to Oracle Database 11g Release  11 . 2 . 0 . 2 . 0  
Connected as IFSAPP
 
SQL> select * from v$version;
 
BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Release  11 . 2 . 0 . 2 . 0  - 64bit Production
PL/SQL Release  11 . 2 . 0 . 2 . 0  - Production
CORE	 11 . 2 . 0 . 2 . 0 	Production
TNS for  64 -bit Windows: Version  11 . 2 . 0 . 2 . 0  - Production
NLSRTL Version  11 . 2 . 0 . 2 . 0  - Production
 
SQL> 
SQL> CREATE TABLE test_x (
   2   ID NUMBER PRIMARY KEY,
   3   NAME VARCHAR2( 30 ),
   4   TYPE VARCHAR2( 30 )
   5   )
   6   /
 
Table created
 
SQL> 
SQL> INSERT INTO test_x
   2   SELECT ROWNUM, object_name,object_type
   3   FROM user_objects;
 
 19635  rows inserted
 
SQL> commit;
 
Commit complete
 
SQL> 
SQL> CREATE OR REPLACE FUNCTION is_customized(name_ IN VARCHAR2) RETURN NUMBER DETERMINISTIC
   2   IS
   3   BEGIN
   4      IF SUBSTR(name_, 1 , 3 ) = 'CF_' THEN
   5         RETURN  1 ;
   6      ELSE
   7         RETURN  0 ;
   8      END IF;
   9   END is_customized;
  10   /
 
Function created
 
SQL> CREATE INDEX test_x_fbi ON test_x( is_customized(NAME) );
 
Index created
 
SQL> BEGIN dbms_stats.gather_table_stats(ownname => USER, tabname => 'TEST_X', CASCADE => TRUE); END;
   2   /
 
PL/SQL procedure successfully completed
 
SQL> 
SQL> SELECT status, funcidx_status FROM user_indexes ui
   2   WHERE ui.INDEX_NAME = 'TEST_X_FBI';
 
STATUS   FUNCIDX_STATUS
-------- --------------
VALID    ENABLED
 
SQL> 
SQL> CREATE OR REPLACE FUNCTION is_customized(name_ IN VARCHAR2) RETURN NUMBER DETERMINISTIC
   2   IS
   3   BEGIN
   4      IF SUBSTR(name_, 1 , 3 ) = 'CF_' THEN
   5         RETURN  1 ;
   6      ELSE
   7         RETURN - 1 ;
   8      END IF;
   9   END is_customized;
  10   /
 
Function created
 
SQL> 
SQL> SELECT status, funcidx_status FROM user_indexes ui
   2   WHERE ui.INDEX_NAME = 'TEST_X_FBI';
 
STATUS   FUNCIDX_STATUS
-------- --------------
VALID    ENABLED
 
SQL> explain plan for
   2   
   2   SELECT COUNT(*) FROM test_x
   3   WHERE is_customized(NAME) =  0  AND TYPE != 'PACKAGE BODY';
 
Explained
 
 
SQL> select * from table(dbms_xplan.display);
 
PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
Plan hash value:  213106679 
--------------------------------------------------------------------------------
| Id  | Operation                    | Name       | Rows  | Bytes | Cost (%CPU)|
--------------------------------------------------------------------------------
|    0  | SELECT STATEMENT             |            |      1  |     10  |     15    ( 0 )|
|    1  |  SORT AGGREGATE              |            |      1  |     10  |            |
|*   2  |   TABLE ACCESS BY INDEX ROWID| TEST_X     |  17999  |   175K|     15    ( 0 )|
|*   3  |    INDEX RANGE SCAN          | TEST_X_FBI |  19635  |       |      4    ( 0 )|
--------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
    2  - filter("TYPE"<>'PACKAGE BODY')
    3  - access("IFSAPP"."IS_CUSTOMIZED"("NAME")= 0 )
 
 16  rows selected
 
SQL>