Modifying Physical Database Definitions › Adding or Dropping Files Associated With an Area

Adding or Dropping Files Associated With an Area

Types of Changes

The pages of an area can be mapped to different files provided that all the pages are accounted for. For example, two files can be combined into one file or one file can be separated into multiple files.

Steps

To add or remove files from an area, follow these steps:

1. Define the new files.
2. Change the definition of the area by excluding all files associated with the area and re-assigning the pages of the area to file blocks.
3. Drop all unused files.
4. Generate, punch and link all DMCLs that contain the segment with which the area is associated.
5. Allocate and format new database files.
6. Make the area to be processed unavailable for update under the central version. (If re-using some of the existing files, take the area offline to the central version.)
7. Backup the area using the AREA option of the BACKUP utility statement and the old DMCL.
8. Restore the area using the AREA option of the RESTORE utility statement and the new DMCL.
9. Make the DMCLs and the new files available to the runtime environment.