Oracle9i New Feature Series: List Partitioning
Oracle9i introduces another type of partitioning in addition
to the RANGE and HASH partitions of 8i. List partitioning lets you create
partitions based on a list of values. For example, if you have a sales table,
and you want to partition the table by the region, you might create the table
as:
- create
table list_example (
- state
char(2),
- amount
number)
- partition
by list (state)
- (
- partition
south values ('TX','LA','OK'),
- partition
north values ('NY','DE','MA'),
- partition others values (DEFAULT)
- )
- /
If you omit the partition name, then Oracle assigns
partition names of the form SYS_Pn
.
The DEFAULT
keyword, introduced in Oracle9i
release 2, creates a partition into which Oracle will insert any row that does
not map to another partition. Therefore, you can specify DEFAULT
for only one partition, and you cannot specify any other values for that
partition. Further, the default partition must be the last partition you define
(similar to the use of MAXVALUE
for range partitions).
The index-organized table cannot be list-partitioned.
Biju Thomas is Oracle7.3 OCP, Oracle8 OCP,
Oracle8i OCP and Oracle9i OCA/OCP Certified DBA |
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