Ikkenull

Ikkenull is a term used in information science and data governance to denote a special missing-value marker that is neither the standard null nor any actual data value. It is used to distinguish deliberate withholding or non-applicability from other forms of missing data in analytical processes.

In data models that support multiple missing-value categories, ikkenull serves as a distinct marker. Semantically, it indicates that the field's value is intentionally withheld or not applicable in a given context, while null indicates that the value is unknown or inapplicable for this record due to system design. This separation can affect queries, aggregations, and privacy-preserving analytics, since ikkenull is treated differently from null in filters and aggregations.

Origin and usage: The term appears in discussions among data engineers and privacy practitioners in the 2010s and 2020s as part of broader conversations about data lineage and responsible analytics. It is not part of formal database standards, and its adoption remains limited to specific organizations or projects. When used, documentation typically defines its semantics and how it interacts with indexing, constraints, and query engines.

See also: Null, NaN, Missing data, Data governance, Privacy-preserving analytics.