Creation of Index on BLOB.

Hello Experts,

Can someone help me in the creation of index on blob & blob is in where clause &  with LIKE operator.  Example query is as below.

 

select CONSUMER_REFERENCE,CORRELID,CONSUMER_ID from subscriptions where UTL_RAW.CAST_TO_VARCHAR2 (DBMS_LOB.SUBSTR(FILTER,500,1)) LIKE 'apos;1-4006675436apos;%';

 

Table description is as below. field in where clause is FILTER, highlighted below.

 

SQL> desc subscriptions;

Name                                      Null?    Type

----------------------------------------- -------- ----------------------------

CONSUMER_REFERENCE                                 VARCHAR2(256)

CORRELID                                  NOT NULL VARCHAR2(256)

TOPIC_EXPRESSION                          NOT NULL VARCHAR2(256)

USE_RAW                                   NOT NULL VARCHAR2(2)

STATUS                                    NOT NULL VARCHAR2(10)

CONTEXT                                            BLOB

FILTER                                             BLOB

CONSUMER_ID                                        VARCHAR2(30)

ORIGINATOR                                         VARCHAR2(30)