Hash Partitioning Redefinition
Description
You can redefine a partition by using the COALESCE PARTITION clause of the ALTER statement. Instances are preserved if the hash partition is redefined.
Syntax
ALTER {TABLE | CLASS} <table_name>
COALESCE PARTITION <unsigned integer>
- table_name : Specifies the name of the table to be redefined.
- unsigned integer : Specifies the number of partitions to be deleted.
Example
The following example shows how to decrease the number of partitions in the nation2 table from 4 to 2.
ALTER TABLE nation2 COALESCE PARTITION 2;
Caution
- Decreasing the number of partitions is only available.
- To increase the number of partitions, use the ALTER TABLE ... ADD PARTITION statement as in range partitioning (see Adding Range Partitioning For details).
- There must be at least one partition remaining after redefining partitions.