Split maxvalue partition in Oracle with new subpartition template - sql

Question

How can I split maxvalue partition in Oracle with new subpartition template.
Or
How can I split maxvalue partition in Oracle and add also add new subpartitions parallely

Answer 1

You can use SPLIT PARTITION as following:
Oracle setup:
SQL> CREATE TABLE PART_EXAMPLE (
2 ID NUMBER,
3 CREATED_DATE DATE
4 )
5 PARTITION BY RANGE (
6 CREATED_DATE
7 )
8 ( PARTITION T1_2019
9 VALUES LESS THAN ( MAXVALUE )
10 );
Table created.
Checking the partitions:
SQL> SELECT
2 TABLE_NAME,
3 PARTITION_NAME
4 FROM
5 USER_TAB_PARTITIONS
6 WHERE TABLE_NAME = 'PART_EXAMPLE';
TABLE_NAME PARTITION_
--------------- ----------
PART_EXAMPLE T1_2019
Splitting the partition into two partitions:
SQL> ALTER TABLE PART_EXAMPLE
2 SPLIT PARTITION T1_2019 AT (TO_DATE('31-DEC-2017 23:59:59', 'DD-MON-YYYY HH24:MI:SS'))
3 INTO (PARTITION T1_2017, PARTITION T1_2019)
4 ONLINE;
Table altered.
Now, Checking the partitions:
SQL> SELECT
2 TABLE_NAME,
3 PARTITION_NAME
4 FROM
5 USER_TAB_PARTITIONS
6 WHERE TABLE_NAME = 'PART_EXAMPLE';
TABLE_NAME PARTITION_
--------------- ----------
PART_EXAMPLE T1_2017
PART_EXAMPLE T1_2019
SQL>
I hope it is clear.
Cheers!!

Answer 2

You can set the subpartitions template for a table. But this only affects new partitions. It has no impact on existing partitions:
create table t (
c1 int, c2 int
) partition by range ( c1 )
subpartition by hash ( c2 )
subpartition template 2
(
partition p0 values less than ( 1 ),
partition pmax values less than ( maxvalue )
);
select partition_name, subpartition_name
from user_tab_subpartitions
where table_name = 'T';
PARTITION_NAME SUBPARTITION_NAME
P0 SYS_SUBP2922
P0 SYS_SUBP2923
PMAX SYS_SUBP2924
PMAX SYS_SUBP2925
alter table t
set subpartition template 1;
select partition_name, subpartition_name
from user_tab_subpartitions
where table_name = 'T';
PARTITION_NAME SUBPARTITION_NAME
P0 SYS_SUBP2922
P0 SYS_SUBP2923
PMAX SYS_SUBP2924
PMAX SYS_SUBP2925
You can also set the template while splitting. But again, this doesn't affect the existing partitions:
alter table t
split partition pmax at ( 2 )
into (
partition p1 set subpartition template 1,
partition pmax set subpartition template 1
);
select partition_name, subpartition_name
from user_tab_subpartitions
where table_name = 'T';
PARTITION_NAME SUBPARTITION_NAME
P0 SYS_SUBP2922
P0 SYS_SUBP2923
P1 SYS_SUBP2926
P1 SYS_SUBP2927
PMAX SYS_SUBP2924
PMAX SYS_SUBP2925
If you want to change the subpartitions while splitting a partition, define them in the subpartitions clause:
alter table t
split partition pmax at ( 3 )
into (
partition p2 subpartitions 1,
partition pmax subpartitions 4
);
select partition_name, subpartition_name
from user_tab_subpartitions
where table_name = 'T';
PARTITION_NAME SUBPARTITION_NAME
P0 SYS_SUBP2936
P0 SYS_SUBP2937
P1 SYS_SUBP2940
P1 SYS_SUBP2941
P2 SYS_SUBP2942
PMAX SYS_SUBP2943
PMAX SYS_SUBP2944
PMAX SYS_SUBP2945
PMAX SYS_SUBP2946