Add sub partition on another column in oracle

Question

I have a table which has two partitions (by range): first_half and second_half based on a column "INSERT_DAY".
I need to add subpartitions "SUCCESS" and "NONSUCCESS" based on the values of another column "STATUS" (subpartition by list) i.e. I need to transform my range partition to composite (range-list) partition.
I do not wish to drop existing tables or partitions. What is the ALTER query for this?
PS: The database is Oracle 9i

Answer 1

Ok, my bad. The project is about charging GPRS customers for data usage.
Here is the real DDL:
CREATE TABLE CDR_EVENT_RCD_FILE_MOB_AGG
   (    "MOBILE_NO" VARCHAR2(16 BYTE),
    "DATA_VOLUME" NUMBER(*,0),
    "CHARGE" NUMBER(*,0),
    "RECORD_COUNT" NUMBER(*,0),
    "COUNTER" NUMBER(*,0) DEFAULT 0,
    "INSERT_DAY" NUMBER(*,0),
    "MAX_FILE_SEQ_NO" NUMBER(*,0),
    "MIN_FILE_SEQ_NO" NUMBER(*,0),
    "REQUEST_ID" VARCHAR2(21 BYTE),
    "TRANSACTION_ID" VARCHAR2(21 BYTE),
    "RESPONSE_TIME" TIMESTAMP (6),
    "RETURN_CODE" CHAR(2 BYTE),
    "FAILURE_REASON" VARCHAR2(1024 BYTE),
    "CHARGED_AMOUNT" NUMBER(*,2)
  PARTITION BY RANGE ("INSERT_DAY")
(PARTITION "FIRST_HALF"  VALUES LESS THAN (16)  ,
PARTITION "SECOND_HALF"  VALUES LESS THAN (MAXVALUE) ) ;
  CREATE INDEX "CDRDEVTBS"."MAX_FILE_SEQ_NO_INDEX" ON "CDRDEVTBS"."CDR_EVENT_RCD_FILE_MOB_AGG" ("MAX_FILE_SEQ_NO") ;
  CREATE INDEX "CDRDEVTBS"."MOBILE_NO_INDEX" ON "CDRDEVTBS"."CDR_EVENT_RCD_FILE_MOB_AGG" ("MOBILE_NO") ;
As you can see, it is partitioned by range on "Insert_day".
The requirement is to delete all the records having counter=3 (which means successful charging) for the records which are older than 15 days.
So I thought, why not create sub partitions with counter so that final DDL would be something like the following. I would then avoid writing a DELETE query, which would take a lot of time to execute.
CREATE TABLE CDR_EVENT_RCD_FILE_MOB_AGG (
    insert_day INT,
    counter INT,
--other columns
PARTITION BY RANGE (insert_day)
SUBPARTITION BY LIST(counter)
SUBPARTITION TEMPLATE
    SUBPARTITION SUCCESS VALUES(3),
    SUBPARTITION NONSUCCESS VALUES(DEFAULT)
    PARTITION first_half VALUES LESS THAN (16),
    PARTITION second_half VALUES LESS THAN (maxvalue)
So that I could execute queries:
alter table CDR_EVENT_RCD_FILE_MOB_AGG  truncate subpartition first_half_success; --execute on last day of every month
alter table CDR_EVENT_RCD_FILE_MOB_AGG  truncate subpartition second_half_success; -- execute on 16th day of every month
to remove unnecessary records.
I would like to create subpartitions without dropping the existing table.