Example 6. DBX and DBY exist, DBZ is to be added

In example 6, DBY must be reorganized to add the logical child pointers to the segment C prefix.

Example 6 is shown in the following figure.

Figure 1. DBX and DBY exist, DBZ is to be added
DBX has SEG A and child SEG B. DB Y has SEG C. DBZ contains SEG D and physical child SEG E. Logical relationship exists between SEG B and SEG C. SEG C is to be the logical parent and child of SEG E.

One of the following three procedures should be used to add the logical child pointers to the segment C prefix:

Procedure when reorganizing DBY (segment B contains a symbolic pointer)

  1. Determine whether the change you are making affects the code in any application programs. If the code is affected, make sure it gets changed.
  2. Unload DBY, using the existing DBD and HD Unload utility.
  3. Code a new DBD for DBY and DBZ.
  4. If the change you are making affected the code in application programs, make any necessary changes to the PSBs for these application programs. If you have the DB/DC Data Dictionary, it can help you determine which application programs and PCBs are affected by the DBD changes you have made.
  5. Rebuild the ACB if you have ACBs prebuilt rather than built dynamically.
  6. Recalculate database space for DBY, and calculate space for DBZ.
  7. For non-VSAM data sets, delete the old database space and define new database space. For VSAM data sets, delete the space allocated for the old clusters and define space for the new clusters.
  8. Run the Prereorganization utility, specifying DBR in the control statement for DBY, and DBIL in the control statement for DBZ. (The output from the Prereorganization utility indicates that a scan of DBX is required.)
  9. Reload DBY, using the new DBD and the HD Reload utility.
  10. Load DBZ, using an initial load program.
  11. Run the Prefix Resolution utility, using the DFSURWF1 work files that are output from Steps 9 and 10 as input.
  12. Run the Prefix Update utility, using the DFSURWF3 work file that is output from Step 11 as input.
  13. Remember to make an image copy of both databases as soon as they are loaded.

When DBY is reloaded, two type 00 records are produced for each occurrence of segment C. One contains a logical child database named DBZ and matches the type 10 record produced for segment E. The other contains a logical child database named DBX. Because a scan or reorganization of DBX was not done, a matching 10 record was not produced for segment B. The Prefix Resolution utility produces message DFS878 when this occurs. The message can be ignored as long as the printed 00 record refers to DBY and DBX. Any messages for DBY and DBZ should be investigated.

Procedure when reorganizing DBY and scanning DBX (segment B contains a direct pointer)

  1. Determine whether the change you are making affects the code in any application programs. If the code is affected, make sure it gets changed.
  2. Unload DBY, using the existing DBD and HD Unload utility.
  3. Code a new DBD for DBY and DBZ.
  4. If the change you are making affected the code in application programs, make any necessary changes to the PSBs for these application programs. If you have the DB/DC Data Dictionary, it can help you determine which application programs and PCBs are affected by the DBD changes you have made.
  5. Rebuild the ACB if you have ACBs prebuilt rather than built dynamically.
  6. Recalculate database space for DBY, and calculate space for DBZ.
  7. For non-VSAM data sets, delete the old database space and define new database space. For VSAM data sets, delete the space allocated for the old clusters and define space for the new clusters.
  8. Run the Prereorganization utility, specifying DBR in the control statement for DBY, and DBIL in the control statement for DBZ. (The output from the Prereorganization utility says that a scan of DBX is required.)
  9. Run the scan utility against DBX.
  10. Reload DBY, using the new DBD and the HD Reload utility.
  11. Load DBZ, using an initial load program.
  12. Run the Prefix Resolution utility, using the DFSURWF1 work files that are output from Steps 9, 10, and 11 as input.
  13. Run the Prefix Update utility, using the DFSURWF3 work file that is output from Step 12 as input.
  14. Remember to make an image copy of both databases as soon as they are loaded.

Procedure when reorganizing DBX and DBY

  1. Determine whether the change you are making affects the code in any application programs. If the code is affected, make sure it gets changed.
  2. Unload DBX and DBY, using the existing DBDs and HD Unload utility.
  3. Code a new DBD for DBY and DBZ.
  4. If the change you are making affected the code in application programs, make any necessary changes to the PSBs for these application programs. If you have the DB/DC Data Dictionary, it can help you determine which application programs and PCBs are affected by the DBD changes you have made.
  5. Rebuild the ACB if you have ACBs prebuilt rather than built dynamically.
  6. Recalculate database space for DBX and DBY, and calculate space for DBZ.
  7. For non-VSAM data sets, delete the old database space and define new database space. For VSAM data sets, delete the space allocated for the old clusters and define space for the new clusters.
  8. Run the Prereorganization utility, specifying DBR in the control statements for DBX and DBY, and DBIL in the control statement for DBZ. (The output from the Prereorganization utility says that a scan of DBX is required.)
  9. Reload DBX and DBY, using the new DBDs and the HD Reload utility.
  10. Load DBZ, using an initial load program.
  11. Run the Prefix Resolution utility, using the DFSURWF1 work files that are output from Steps 9 and 10 as input.
  12. Run the Prefix Update utility, using the DFSURWF3 work file that is output from Step 11 as input.
  13. Remember to make an image copy of all three databases as soon as they are loaded.