The DBSPACE Reorganization Tool tool makes it easy to manage your database servers.
Databases are composed of many DBSPACEs that are logical allocations of space. DBSPACEs can contain one or more tables and their indexes. DBSPACE reorganizations are critical for providing optimum database performance because when you DROP and re-ACQUIRE a DBSPACE, all unused DBSPACE pages are returned to the storage pool for use elsewhere.
Control Center's ability to backup, copy, move, and migrate DBSPACEs gives you control and flexibility in managing database growth. It also allows you to extract all of the Data Definition Language (DDL) statements needed to re-create a DBSPACE and everything in it. DBAs no longer have to manage huge libraries of DDL or struggle to produce "where-used" information because Control Center does it for them.
The DBSPACE Reorganization Tool tool operates in Multiple User Mode (MUM) or Single User Mode (SUM). You can choose the mode to run in. (MUM jobs run in one partition while the database is up and running in another, available for other users and applications. A SUM application starts the database. As soon as the database is up, the application program takes control, so both are running in the same partition. Other users cannot access the database until the SUM job ends and the database is restarted in MUM).
Reorganization jobs run in batch and consist of several job steps. Each job step is assigned a step number and description. DLBLs are generated for each step and are included in the JCL so that you know what files are being accessed.
The Control Center screen collects parameters needed by the batch programs. The DBSPACE Reorganization Submit screen, displayed when you press ENTER from the Reorganization screen, allows you to schedule jobs for execution immediately or at a later date and time, and on a one-time or repetitive basis.