Example 2: FIX hash partitioning

Nonstop Database, HiRDB Version 9 System Operation Guide

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 the RDAREAs into which data is to be loaded; (7) Use the pdload command to load data into TABLE01; (8) Back up the RDAREAs in which data was loaded; (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 -W bin -t TABLE01 -g /pdrorg/unld02

Explanation: -k: Specifies unld for unloading.; -W bin: Specifies that the unload data file is to be used as the input file (binary format) for the pdload command.; -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 configuration. 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 the RDAREAs into which data is to be loaded

 
pdhold -r RDAREA01,RDAREA02,...

(7) Use the pdload command to load data into TABLE01

 
pdload -b -W TABLE01 /pdload/load02

Explanation: -b: Specifies that binary data is to be loaded.; -W: Specifies that binary format input data created by the pdrorg command is to be used.; TABLE01: Specifies the name of the table into which data is to be loaded.; /pdload/load02: Specifies the name of the control statements file for the pdload command.

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

Because you loaded data in the pre-update acquisition mode (default), back up the RDAREAs in which data was loaded. For details about backing up RDAREAs, see 6.4.8 Example 8 (backing up specified RDAREAs).

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

 
pdrels -r RDAREA01,RDAREA02,...

We recommend that after the command has executed you check whether the execution results are correct. For details on how to check command execution results, see the manual HiRDB Version 9 Command Reference.