13.14.2 Example 2: FIX hash partitioning

This example changes to HASH6 the hash function of table TABLE01. TABLE01 is flexible hash partitioned.

Organization of this subsection
(1) Use the pdhold command to shut down RDAREAs to be unloaded
(2) Use the pdrorg command to unload data from TABLE01
(3) Use the pdrels command to release RDAREAs from shutdown status
(4) Use the PURGE TABLE statement to delete TABLE01's data
(5) Use the ALTER TABLE statement to change the hash function
(6) Use the pdhold command to shut down RDAREAs to be reloaded
(7) Use the pdrorg command to reload data into TABLE01
(8) Back up the RDAREAs in which data was reloaded
(9) Use the pdrels command to release RDAREAs from shutdown status

(1) Use the pdhold command to shut down RDAREAs to be unloaded

pdhold -r RDAREA01,RDAREA02,...

(2) Use the pdrorg command to unload data from TABLE01

pdrorg -k unld -j -t TABLE01 -g /pdrorg/unld02

Explanation
-k: Specifies unld for unloading.
-j: Specifies that a LOB column or a column with the LOB attribute is defined in the table that is to be unloaded.
-t: Specifies the name of the table that is to be unloaded.
-g: Specifies that TABLE01 is row-partitioned between servers in a HiRDB/Parallel Server. Specifying the -g option consolidates the unload data files (into a single file).
/pdrorg/unld02: Specifies the name of the control statements file for the pdrorg command.

(3) Use the pdrels command to release RDAREAs from shutdown status

pdrels -r RDAREA01,RDAREA02,...

(4) Use the PURGE TABLE statement to delete TABLE01's data

PURGE TABLE TABLE01;

When the hash function of a table with FIX hash partitioning is changed, the table data must be deleted.

(5) Use the ALTER TABLE statement to change the hash function

ALTER TABLE TABLE01 CHANGE HASH HASH6;

(6) Use the pdhold command to shut down RDAREAs to be reloaded

pdhold -r RDAREA01,RDAREA02,...

(7) Use the pdrorg command to reload data into TABLE01

pdrorg -k reld -j -t TABLE01 -g /pdrorg/reld02

Explanation
-k: Specifies reld for reloading.
-j: Specifies that a LOB column or a column with the LOB attribute is defined in the table that is to be reloaded.
-t: Specifies the name of the table that is to be reloaded.
-g: If the -g option was specified in step (2), specify it here as well.
/pdrorg/reld02: Specifies the name of the control statements file for the pdrorg command.

(8) Back up the RDAREAs in which data was reloaded

Because you reloaded data in the pre-update acquisition mode (default), back up the RDAREAs in which data was reloaded. For details about backing up RDAREAs, see 6.4.6 Example 6 (Backing up RDAREAs).

(9) Use the pdrels command to release RDAREAs from shutdown status

pdrels -r RDAREA01,RDAREA02,...

It is recommended that after the command has executed you check whether or not the execution results are correct. For details on how to check command execution results, see the manual HiRDB Version 8 Command Reference.