The scope of HALDB database modifications
When you modify HALDB databases, you need to be aware of the scope of your changes. Some of the changes that you can make affect only one partition or a subset of partitions. Other changes to HALDB databases affect the entire database and all of its partitions.
The following table provides a list of typical HALDB database changes, where you specify the change, and the scope of the change.
| What you are modifying | Where you specify the change | The scope of the change | Notes |
|---|---|---|---|
| Field definition, adding or deleting | DBD statements | Entire HALDB database and its partitions | The HALDB database must be unloaded only if you are changing field offsets or the length of a segment |
| Data capture exit routine | DBD statements | Entire HALDB database and its partitions | Does not require an unload of the HALDB database |
| Segment type, adding or deleting | DBD statements | Entire HALDB database and its partitions | The HALDB database must be unloaded |
| Pointer options | DBD statements | Entire HALDB database and its partitions | The HALDB database must be unloaded |
| Segment Edit/Compression exit routine | DBD statements | Entire HALDB database and its partitions | The HALDB database must be unloaded |
| Selection criteria of a HALDB partition selection exit routine | DBD statements and the RECON data set | Only the partitions that are impacted by the change in the distribution of records by the partition selection exit routine | You must unload only the partitions that are impacted by the change in record distribution |
| Data set name prefix | The RECON data set | Only the specified partition | Only the affected partition is unauthorized, access to all other partitions is unaffected |
| Randomizing module or randomizing parameters | DBD statements, the RECON data set, or both | If made in the DBD, all partitions in the database. If made in the RECON data set, only the specified partition | For changes to the specifications in the RECON data set, only the affected partition is unauthorized, access to all other partitions is unaffected |
| High keys of partitions | The RECON data set | All partitions affected by the change in record distribution introduced by the new or changed high key | You must unload only the partitions affected by the change in record distribution |