Examples of single partition processing of a PSINDEX

The following examples illustrate the circumstances in which the FM, GE, and GB status codes are returned to an application program that is restricted to processing a single partition of a HALDB partitioned secondary index (PSINDEX).

In all of the examples, the DB PCB usage is restricted to a partition that contains records with secondary index keys 201 through 400. Partition 2 of the PSINDEX references multiple partitions in the indexed HALDB database.

GU xdfldkey=110

The root key 110 is outside the range of root keys for the partition. IMS returns an FM status code.

GU xdfldkey=240 GN xdfldkey=110

The processing moves forward from root key 240 to find a key that is equal to 110. Because 110 is lower than 240, IMS returns a GE status code.

GU xdfldkey=240 GN xdfldkey>=110

The processing moves forward from root key 240 to find a key that is equal to or greater than 110. If the key is not found before reaching the end of the partition, IMS returns a GB status code.

GN xdfldkey>=110

The processing attempts to start the search at key 110. Because the key is outside of the root key range of the partition, IMS returns an FM status code.