<database> A kind of database management system that links records together like a family tree such that each record type has only one owner, e.g. an order is owned by only one customer. Hierarchical structures were widely used in the first mainframe database management systems. However, due to their restrictions, they often cannot be used to relate structures that exist in the real world.
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Nearby terms: HIBOL « HID « hidden flag « hierarchical database » Hierarchical Data Format » Hierarchical Design Methodology » hierarchical file system