Perustunnus

Perustunnus is a Finnish term used in information management to denote a core, unique identifier assigned to an entity within a data system. It functions as a primary key that enables unambiguous reference and linking of records across datasets, supporting data integration and cross-system queries. The exact meaning and use of a perustunnus vary by system and organization; it is not a universally standardized identifier, but a design construct within a particular data model or register.

In Finnish public administration and in various information systems, perustunnus may be used for different entity types such as persons, organizations, properties, or other objects, depending on the context and the data architecture. The identifier is typically intended to be persistent and stable over time to maintain referential integrity, even as other attributes of the record may change.

Relation to other identifiers: Finland uses several well-known identifiers such as henkilötunnus (personal identity number), Y-tunnus (business ID), and kiinteistötunnus (property parcel ID). Perustunnus is a more generic, system-specific key that may coexist with these identifiers or be used as the primary key within a particular dataset, rather than replacing national identifiers.

Implementation and governance considerations include ensuring uniqueness, defining the lifecycle and change management of the identifier, and establishing mappings to other identifiers when data is exchanged between systems. Privacy, data quality, and auditability are important aspects in the design and use of a perustunnus.

See also: unique identifiers, data governance, data integration, kiinteistötunnus, henkilötunnus, Y-tunnus.