Executor: HiRDB administrator and table owner

When there are significant differences from one RDAREA to another in terms of the number of rows stored in the RDAREAs, processing efficiency for the table might degrade. In such a case, you can improve the table's processing efficiency by changing the hash function so as to equalize the numbers of rows stored in the RDAREAs.

Notes

1. Changing the hash function of a table invalidates any stored routines that use that table. If this happens, use the ALTER PROCEDURE or ALTER ROUTINE statement to re-create each stored routine.
2. Changing the hash function of a table specified in a trigger SQL statement invalidates the trigger. If this happens, use the ALTER TRIGGER or ALTER ROUTINE statement to re-create the trigger.
3. After the hash function has been changed, execute the optimizing information collection utility (pdgetcst command) if necessary. For details about whether execution of the optimizing information collection utility is required, see the manual HiRDB Version 9 Command Reference.
4. The hash function can be changed for a table in which an abstract data type is defined of a plug-in that has the constructor reverse generation function.

Organization of this section

13.14.1 Example 1: Flexible hash partitioning

13.14.2 Example 2: FIX hash partitioning