We recommend using the inner replica facility because you can reference and update the database while reorganizing it. This is called updatable online reorganization. If the inner replica facility is not used, the database cannot be referenced or updated while it is being reorganized. Using the inner replica facility minimizes the impact on online job tasks because job processing uses the replica database while the master database is being reorganized. The following figure shows how to reorganize a database using the inner replica facility.

Figure D-2 Database reorganization using the inner replica facility

Explanation

The database reorganization utility (prdorg command) is used to reorganize the master database, and the replica database is used for the online job tasks.

Before reorganizing the current database, another database is committed and the current database is switched to that database. The current database cannot be referenced or updated during this time. After the current database is switched, the master database is reorganized and the replica database is used for performing online job tasks. After reorganization is complete, the system log for the replica database becomes input information and the update processes performed during the reorganization are applied to the master database. This is called reflection processing.

For details about the inner replica facility, see the HiRDB Version 9 Staticizer Option Description and User's Guide.

When the inner replica facility is not used

When the inner replica facility is not used, a table being reorganized is placed in the lock mode (EX). Therefore, we recommend that you use the pdhold command to place the RDAREA that stores the table to be reorganized in shutdown status so that the UAP will not wait for lock-release. UAPs that were accessing in the reorganization table are terminated immediately without waiting for lock-release because RDAREAs in hold status cannot be accessed. Set in the reorganization table the amount of time RDAREAs will not be accessible, and. reorganize the table within that amount of time.