You can run the ALTER TABLE...MERGE SUBPARTITION command to merge two subpartitions into a new subpartition that contains all the content of the two original subpartitions.

Note
  • You must be the owner of the table or have administrative permissions on the table to execute the statement.
  • This SQL command can be used only in the LIST partitioned table and the RANGE partitioned table. It cannot be used in the HASH partitioned table.
  • If indexes exist on the table, the indexes will be created on the new partition.

Syntax

ALTER TABLE table_name MERGE SUBPARTITIONS
        partition_name , partition_name 
        INTO SUBPARTITION  new_part [TABLESPACE tablespace_name] ;

Parameters

Parameter Description
table_name The name of the partitioned table. You can specify a schema.
partition_name The names of the two subpartitions to be merged. Separate the names with commas (,).
new_part The name of the new subpartition.

Partition names must be unique among all partitions and subpartitions.
tablespace_name Specifies the tablespace in which the new subpartition resides.

If you do not specify a tablespace, the subpartition will reside in the default tablespace.

Examples

Create a partitioned table named sales and insert test data into the table. Example: 

CREATE TABLE sales
(
  dept_no     number,   
  part_no     varchar2,
  country     varchar2(20),
  date        date,
  amount      number
)
PARTITION BY LIST(country)
  SUBPARTITION BY RANGE(date)
(
  PARTITION europe VALUES('FRANCE', 'ITALY')
    (
      SUBPARTITION europe_2011 
        VALUES LESS THAN('2012-Jan-01'),
      SUBPARTITION europe_2012 
        VALUES LESS THAN('2013-Jan-01')
    ),
  PARTITION asia VALUES('INDIA', 'PAKISTAN')
    (
      SUBPARTITION asia_2011 
        VALUES LESS THAN('2012-Jan-01'),
      SUBPARTITION asia_2012 
        VALUES LESS THAN('2013-Jan-01')
    ),
  PARTITION americas VALUES('US', 'CANADA')
    (
      SUBPARTITION americas_2011 
        VALUES LESS THAN('2012-Jan-01'),
      SUBPARTITION americas_2012 
        VALUES LESS THAN('2013-Jan-01')
    )
);
SELECT partition_name, subpartition_name, high_value FROM ALL_TAB_SUBPARTITIONS where table_name = 'SALES';
INSERT INTO sales VALUES
  (10, '4519b', 'FRANCE', '17-Jan-2012', '45000'),
  (20, '3788a', 'INDIA', '01-Mar-2012', '75000'),
  (40, '9519b', 'US', '12-Apr-2012', '145000'),
  (20, '3788a', 'PAKISTAN', '04-Jun-2012', '37500'),
  (40, '4577b', 'US', '11-Nov-2012', '25000'),
  (30, '7588b', 'CANADA', '14-Dec-2012', '50000'),
  (30, '9519b', 'CANADA', '01-Feb-2012', '75000'),
  (30, '4519b', 'CANADA', '08-Apr-2012', '120000'),
  (40, '3788a', 'US', '12-May-2012', '4950'),
  (10, '9519b', 'ITALY', '07-Jul-2012', '15000'),
  (10, '9519a', 'FRANCE', '18-Aug-2012', '650000'),
  (10, '9519b', 'FRANCE', '18-Aug-2012', '650000'),
  (20, '3788b', 'INDIA', '21-Sept-2012', '5090'),
  (40, '4788a', 'US', '23-Sept-2012', '4950'),
  (40, '4788b', 'US', '09-Oct-2012', '15000'),
  (20, '4519a', 'INDIA', '18-Oct-2012', '650000'),
  (20, '4519b', 'INDIA', '2-Dec-2012', '5090');
SELECT tableoid::regclass, * FROM sales;

Split the americas_2012 subpartition into two subpartitions: americas_p1_2012 and americas_p2_2012. Example: 

ALTER TABLE sales 
  SPLIT SUBPARTITION americas_2012 
  AT('2012-Jun-01')
  INTO
  (
    SUBPARTITION americas_p1_2012, 
    SUBPARTITION americas_p2_2012
  );

Merge the americas_p1_2012 and americas_p2_2012 subpartitions into a new subpartition new_americas_2012. Example: 

ALTER TABLE sales 
  MERGE SUBPARTITIONS americas_p1_2012 ,americas_p2_2012
  INTO  SUBPARTITION new_americas_2012;