A DL/I secondary index involves a primary database and an index database. The primary database contains a source and a target segment. The index database contains an index pointer segment, which is also the root segment.
Define Index Pointer Segment as Member Record
In CA IDMS DLI Transparency, the index pointer segment is defined as a member record type with a location mode of VIA in a set owned by the target record. The pointer segment is also defined as a member record in a system-owned indexed set. This set is sorted in ascending order on the pointer record's symbolic key, which is equivalent to the sequence field in the pointer segment.
CA IDMS/DB does not require a separate set to reflect the source segment and pointer segment relationship.
Implementing Pointer and Target Relationships in CA IDMS/DB
The illustration below illustrates the CA IDMS/DB set structure that relates the pointer and target segments. Note that this relationship is the same for a secondary index and a HIDAM index database.
Figure 25. CA IDMS/DB implementation of pointer and target relationship
DL/I Secondary Index and CA IDMS/DB Sets
The following diagram shows a secondary index for an HDAM primary database and the corresponding CA IDMS/DB set structures. Note that the primary database is an HDAM database and the pointer segment is in the index (secondary) database.
Figure 26. DL/I secondary index and corresponding CA IDMS/DB sets
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