Workaround for ORA-14634 during an attempt to split a partition containing subpartitions

Short background:
I had a LIST/RANGE partitioned tables that needed a new partition.

The table is partitioned BY LIST on column STREAM, and subpartitioned BY RANGE on column LASTUPDATED. 

Each subpartition is placed in a tablespace according to the year in the LASTUPDATED column. 

So for example, no matter which partition the subpartition belongs to, it will always go into tablespace DATA_2019 if the LASTUPDATED column has a value which falls within the boundaries of year 2019. 

This is called vertically striping of partitions and is often, but now always, set up using a subpartition template.

DDL for the table:

  CREATE TABLE CATEGORIES
(
  UID              VARCHAR2(255 BYTE),
  CREATED          TIMESTAMP(6)                 NOT NULL,
  LASTUPDATED      TIMESTAMP(6)                 NOT NULL,
  BODY             CLOB,
  STREAM           VARCHAR2(255 BYTE)
)
LOB (SBODY) STORE AS SECUREFILE BLOB (
  TABLESPACE  DATA1
  ENABLE      STORAGE IN ROW
  CHUNK       8192
  COMPRESS    MEDIUM
)
COMPRESS FOR OLTP
TABLESPACE DATA1
PARTITION BY LIST (STREAM)
SUBPARTITION BY RANGE (LASTUPDATED)
(
 -- partition definition ..
 	-- subpartition definition..
);
  

I had the following SQL intended to split the partition OTHERS into a brand new partition called DIGITAL_MEDIA:

ALTER TABLE categories
 SPLIT PARTITION OTHERS VALUES
 ('audiobooks')
 INTO (
       PARTITION DIGITAL_MEDIA
       TABLESPACE DATA1
     (
     	 -- 2016
        SUBPARTITION SP_dm_older 
        VALUES LESS THAN ( TO_DATE('2016-01', 'YYYY-MM')) TABLESPACE DATA1,
        subpartition SP_dm_201601 
        VALUES LESS THAN (TO_DATE(' 2016-02-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS')) TABLESPACE DATA_2016,
        LOB (BLOB) STORE AS SECUREFILE  ( TABLESPACE DATA_2016 ),
        VALUES LESS THAN (TO_DATE(' 2016-03-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS')) TABLESPACE DATA_2016,
        LOB (BLOB) STORE AS SECUREFILE  ( TABLESPACE DATA_2016 ),
        .
        .
        .
        subpartition SP_dm_202411 
        VALUES LESS THAN (TO_DATE(' 2024-12-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS')) TABLESPACE DATA_2024
        LOB (BLOB) STORE AS SECUREFILE  ( TABLESPACE ATOMHOPPER_2024 ),
        subpartition SP_dm_202412 
        VALUES LESS THAN (TO_DATE(' 2025-01-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS')) TABLESPACE DATA_2024
        LOB (BLOB) STORE AS SECUREFILE  ( TABLESPACE DATA_2024 ),
        SUBPARTITION SP_DM_DEFAULT VALUES LESS THAN (MAXVALUE) TABLESPACE DATA1
        LOB (BLOB) STORE AS SECUREFILE  ( TABLESPACE DATA1)
        )
     ,
PARTITION OTHERS
)
ONLINE
UPDATE GLOBAL INDEXES;

There were a total of 110 subpartitioned listed in the above DDL. When trying to execute the script, I received:

ORA-14634: Subpartition descriptions cannot be specified during the SPLIT/MERGE of a partition of a Range-List partitioned table

Looking it up:

oerr ora 14634
// *Cause:  During a split or a merge of a partition of a range list
//          partitioned table you cannot specify any subpartitioning
//          information for the resulting partition (s)
// *Action: Remove all subpartitioning information from the DDL.

A rather clear message, which I followed, and thus changed my DDL to this:

ALTER TABLE categories
 SPLIT PARTITION OTHERS VALUES
 ('audiobooks')
 INTO (
       PARTITION DIGITAL_MEDIA
     , PARTITION OTHERS)
ONLINE
UPDATE GLOBAL INDEXES;

indeed a much simpler syntax.

 
It parsed without errors, and the result was a new partition, with system-generated names, placed in the correct tablespaces.

Let's verify the results:

SELECT table_name,partition_name,subpartition_name,tablespace_name
FROM DBA_TAB_SUBPARTITIONS 
WHERE TABLE_NAME='CATEGORIES' 
AND PARTITION_NAME='DIGITAL_MEDIA';
 

TABLE_NAME	PARTITION_NAME	SUBPARTITION_NAME	TABLESPACE_NAME
CATEGORIES	DIGITAL_MEDIA	SYS_SUBP39427	DATA_2016
CATEGORIES	DIGITAL_MEDIA	SYS_SUBP39428	DATA_2016
CATEGORIES	DIGITAL_MEDIA	SYS_SUBP39429	DATA_2016
CATEGORIES	DIGITAL_MEDIA	SYS_SUBP39527	DATA_2024
CATEGORIES	DIGITAL_MEDIA	SYS_SUBP39528	DATA_2024
CATEGORIES	DIGITAL_MEDIA	SYS_SUBP39529	DATA_2024

The fact that we for this particular partition now must deal with system generated names is of no importance. The optimizer will still use partition pruning when appropriate.