Interval partitioning

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What is interval partitioning?

Samples

  • Create a RANGE-partitioned table with one partition.
CREATE TABLE SALES (
    PRODUCT_NAME        VARCHAR2(50),
		TRANSACTION_DATE    DATE,
		SALE_PRICE          NUMBER(10,2),
    AMOUNT_SOLD         NUMBER
)
PARTITION BY RANGE (TRANSACTION_DATE)
INTERVAL(NUMTOYMINTERVAL(1, 'MONTH')) 
(
    PARTITION P1 values less than (TO_DATE('03-01-2011','MM-DD-YYYY'))
);

Table created
  • Table can be created on multiple tablespaces if needed.
CREATE TABLE SALES (
    PRODUCT_NAME        VARCHAR2(50),
		TRANSACTION_DATE    DATE,
		SALE_PRICE          NUMBER(10,2),
    AMOUNT_SOLD         NUMBER
)
PARTITION BY RANGE (TRANSACTION_DATE)
INTERVAL(NUMTOYMINTERVAL(1, 'MONTH')) STORE IN (tbs1, tbs2, tbs3, tbs4) 
(
    PARTITION P1 values less than (TO_DATE('03-01-2011','MM-DD-YYYY'))
);

Table created
  • Verify the partition creation.
SQL> column TABLE_NAME format A10
SQL> column PARTITION_NAME format A8

SQL> SELECT table_name, partition_name, high_value FROM user_tab_partitions
WHERE table_name='SALES';

TABLE_NAME PARTITIO HIGH_VALUE
---------- -------- --------------------------------------------------------------------------------
SALES      P1       TO_DATE(' 2011-03-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
 
  • Insert a value within the created partition -> No new partition created.
SQL> insert into SALES values ('XOOM','01-FEB-11', 600, 30000);
 
1 row inserted
 
SQL> SELECT table_name, partition_name, high_value FROM user_tab_partitions
  2  WHERE table_name='SALES';
 
TABLE_NAME PARTITIO HIGH_VALUE
---------- -------- --------------------------------------------------------------------------------
SALES      P1       TO_DATE(' 2011-03-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
  • Insert a value higher than the threshold of the initial partition. Expected a new partition with new one-month range.
SQL> insert into SALES values ('DROID','15-MAR-11', 20, 50000);
 
1 row inserted
 
SQL> SELECT table_name, partition_name, high_value FROM user_tab_partitions
  2  WHERE table_name='SALES';
 
TABLE_NAME PARTITIO HIGH_VALUE
---------- -------- --------------------------------------------------------------------------------
SALES      P1       TO_DATE(' 2011-03-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
SALES      SYS_P81  TO_DATE(' 2011-04-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
 
  • Insert a value couple months in advance. New partition is created. However, there is a gap still UN-MATERIALIZED.
SQL> insert into SALES values ('DROID2','15-JUL-11', 30, 70000);
 
1 row inserted
 
SQL> SELECT table_name, partition_name, high_value FROM user_tab_partitions
  2  WHERE table_name='SALES';
 
TABLE_NAME PARTITIO HIGH_VALUE
---------- -------- --------------------------------------------------------------------------------
SALES      P1       TO_DATE(' 2011-03-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
SALES      SYS_P81  TO_DATE(' 2011-04-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
SALES      SYS_P82  TO_DATE(' 2011-08-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
  • Insert a value in between that un-materialized gap.
 
SQL> insert into SALES values ('DROID PRO','15-JUN-11', 300, 65000);
 
1 row inserted
 
SQL> SELECT table_name, partition_name, high_value FROM user_tab_partitions
  2  WHERE table_name='SALES';
 
TABLE_NAME PARTITIO HIGH_VALUE
---------- -------- --------------------------------------------------------------------------------
SALES      P1       TO_DATE(' 2011-03-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
SALES      SYS_P81  TO_DATE(' 2011-04-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
SALES      SYS_P83  TO_DATE(' 2011-07-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'
SALES      SYS_P82  TO_DATE(' 2011-08-01 00:00:00', 'SYYYY-MM-DD HH24:MI:SS', 'NLS_CALENDAR=GREGORIA'

Can I change the interval after partitions are created already?

See Also