Planual Rules regarding Subsets in the classic Hyperblock engine.

Note: Rule numbers on this page may not be sequential. Our Planual uses a common index across Classic Hyperblock and Polaris Engines, which means some rules only appear on one page or may have been removed.

Always prefix subset names with the name of their parent list. Use a standard format such as Parent List Name]: [Subset Description] (for example, P3 Products: Active Products). Adhering to this naming convention improves auditability, particularly when navigating large models with numerous subsets.
Engine Applicability: Classic Hyperblock and Polaris

Lists and subsets take up space within a model, so if you need multiple subsets of the same list, consider whether they would be better as separate lists. This is especially valid if the lists don't overlap and they're being fed from a Data Hub. For overlapping subsets or if there is a need to “consolidate” the value back to the primary list then subsets are a valid construct for model efficiency.

If possible, try and avoid single item subsets. If there's a top level in the list, a single item subset will always have two members. Consider using a Boolean flag in a SYS module or a LOOKUP line item against the desired item (to avoid using SELECT).