Oracle partitioning by range - sql

Question

I need to split the table into partitions, namely into three partitions according to the EVENT_TIME field, where the first partition is an interval of a week from today, the second last week and the third partition is history, where data that does not pass into the first two partitions are placed.
In addition, I need to add a trigger that will clear the history every two weeks.
CREATE TABLE EVENTS_LOG_TEST_PARTITION
(
ID NUMBER,
METHOD NVARCHAR2(100),
INPUT CLOB,
EVENT_TIME TIMESTAMP(6),
STATUS NVARCHAR2(100),
MESSAGE NVARCHAR2(200)
)
PARTITION BY RANGE (EVENT_TIME)
(
PARTITION CURRENT_WEEK VALUES LESS THAN (TO_DATE(TO_CHAR(CURRENT_TIMESTAMP), 'dd-MM-yyyy HH24:mi:ss'))
)
ENABLE ROW MOVEMENT;
I know that this is not a valid request, so I am writing, please help

Answer 1

It sounds like you want to keep a rolling 2-3 weeks' worth of data. In which case you can use interval partitioning, dropping the oldest partition each week.
Interval partitioning creates a new partition whenever you insert a row with a value greater than the current highest partition boundary.
All you need to define is an initial partition and the time interval. You can choose any value in the past as the boundary for the initial partition.
For example:
create table events_log_test_partition (
id number,
method nvarchar2(100),
input clob,
event_time timestamp(6),
status nvarchar2(100),
message nvarchar2(200)
) partition by range (event_time)
interval ( interval '7' day ) (
partition p_init values less than ( date'2021-01-04' )
);
insert into events_log_test_partition
values ( 1, 'test', 'test', systimestamp - 14, 'test', 'test' );
insert into events_log_test_partition
values ( 2, 'test', 'test', systimestamp, 'test', 'test' );
select partition_name, high_value
from user_tab_partitions
where table_name = 'EVENTS_LOG_TEST_PARTITION';
/*
PARTITION_NAME HIGH_VALUE
P_INIT TIMESTAMP' 2021-01-04 00:00:00'
SYS_P6002 TIMESTAMP' 2021-08-23 00:00:00'
SYS_P6005 TIMESTAMP' 2021-09-06 00:00:00'
*/
select * from events_log_test_partition
partition for ( date'2021-08-18' );
/*
ID METHOD INPUT EVENT_TIME STATUS MESSAGE
1 test test 18-AUG-2021 13.09.17.000000000 test test
*/
select * from events_log_test_partition
partition for ( date'2021-09-01' );
/*
ID METHOD INPUT EVENT_TIME STATUS MESSAGE
2 test test 01-SEP-2021 13.09.17.516073000 test test
*/
alter table events_log_test_partition
drop partition for ( date'2021-08-18' );
select partition_name, high_value
from user_tab_partitions
where table_name = 'EVENTS_LOG_TEST_PARTITION';
/*
PARTITION_NAME HIGH_VALUE
P_INIT TIMESTAMP' 2021-01-04 00:00:00'
SYS_P6005 TIMESTAMP' 2021-09-06 00:00:00'
*/