Oracle??™s Partitioning Option enables data partitions based on business value ranges
(such as date) or discrete values for administrative flexibility, while enhancing query
performance through the cost-based optimizer??™s ability to eliminate access to nonrelevant
partitions. For example, ???rolling window??? administrative operations can be
used to add new data and remove old data using time ranges. A new partition can be
added, loaded, and indexed in parallel, and optionally removed, all without impacting
access to existing data.
Range partitioning first became available in the Oracle8 Partitioning Option. Hash
partitioning was added to the Oracle8i Partitioning Option enabling the spread of
data evenly based on a hash algorithm for performance. Hashing may be used within
range partitions (composite partitioning) to increase the performance of queries while
still maintaining the manageability offered by range partitioning. Oracle9i introduced
list partitioning??”partitions based on discrete values such as geographies. A
composite partitioning type, range-list partitioning, which allows youto partition by
dates within geographies, was added in Oracle9i Release 2.
Pages:
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521