使用复合分区,例如范围(用于您的时间维度)和列表(以区分应该保持长时间和有限时间的行。
例子
带有的行KEEP_ID='N'
应在 5 个月后消除。
CREATE TABLE tab
( id NUMBER(38,0),
trans_dt DATE,
keep_id VARCHAR2(1)
)
PARTITION BY RANGE (trans_dt) INTERVAL (NUMTOYMINTERVAL(1,'MONTH'))
SUBPARTITION BY LIST (keep_id)
SUBPARTITION TEMPLATE
( SUBPARTITION p_catalog VALUES ('Y'),
SUBPARTITION p_internet VALUES ('N')
)
(PARTITION p_init VALUES LESS THAN (TO_DATE('01-JAN-2019','dd-MON-yyyy'))
);
填充 6 个月的样本数据
insert into tab (id, trans_dt, keep_id)
select rownum, add_months(date'2019-08-01', trunc((rownum-1) / 2)), decode(mod(rownum,2),0,'Y','N')
from dual connect by level <= 12;
select * from tab
order by trans_dt, keep_id;
ID TRANS_DT KEEP_ID
---------- ------------------- -------
1 01.08.2019 00:00:00 N --- this subpartition should be deleted
2 01.08.2019 00:00:00 Y
3 01.09.2019 00:00:00 N
4 01.09.2019 00:00:00 Y
5 01.10.2019 00:00:00 N
6 01.10.2019 00:00:00 Y
7 01.11.2019 00:00:00 N
8 01.11.2019 00:00:00 Y
9 01.12.2019 00:00:00 N
10 01.12.2019 00:00:00 Y
11 01.01.2020 00:00:00 N
12 01.01.2020 00:00:00 Y
现在使用分区扩展名来引用应该删除的子分区。
删除超过 5 个月的子分区,但仅适用于 KEEP_ID = 'N'
alter table tab drop subpartition for (DATE'2019-08-01','N');
新数据
ID TRANS_DT KEEP_ID
---------- ------------------- -------
2 01.08.2019 00:00:00 Y
3 01.09.2019 00:00:00 N
4 01.09.2019 00:00:00 Y
.....