Execution plan image:
Partition operation.
A partitioned table is comprised of multiple segments. Each segment contains table rows that share the same range of values for a particular column. A table (and its indexes) can be range partitioned.
CREATE TABLE sales_range_part
(column definitions)
PARTITION BY RANGE (sale_date)
(PARTITION q198 VALUES LESS THAN
(TO_DATE('1998-04-01', 'YYYY-MM-DD')) ,
PARTITION q298 VALUES LESS THAN
(TO_DATE('1998-07-01', 'YYYY-MM-DD')) ,
PARTITION q398 VALUES LESS THAN
(TO_DATE('1998-10-01', 'YYYY-MM-DD')) ,
PARTITION q498 VALUES LESS THAN
(TO_DATE('1999-01-01', 'YYYY-MM-DD')) ,
PARTITION q199 VALUES LESS THAN
(TO_DATE('1999-04-01', 'YYYY-MM-DD')) ,
PARTITION q299 VALUES LESS THAN
(TO_DATE('1999-07-01', 'YYYY-MM-DD')) ,
PARTITION q399 VALUES LESS THAN
(TO_DATE('1999-10-01', 'YYYY-MM-DD')) ,
PARTITION q499 VALUES LESS THAN
(TO_DATE('2000-01-01', 'YYYY-MM-DD')) ,
PARTITION q100 VALUES LESS THAN
(TO_DATE('2000-04-01', 'YYYY-MM-DD')) ,
PARTITION q200 VALUES LESS THAN
(TO_DATE('2000-07-01', 'YYYY-MM-DD')) )
Each partition is a separate segment, and partitions can be stored in separate tablespaces and have individual storage definitions. Although partitions are implemented transparently to an application and need not be specified in SQL, SQL statements can specify a partition name. For instance, the following statement applies an update to an individual partition (S1) only:
UPDATE sales_part PARTITION(s1)
SET purge_ind=’Y’
WHERE sale_value < 10000
The RECURSIVE EXECUTION operation executes a statement with a recursive execution function call.
The RECURSIVE WITH PUMP operation executes a self-join operation in hierarchical fashion.
The REFERENCE MODEL operation retrieves data from a reference table.
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