EffectiveTo

EffectiveTo is a data field used in effective dating to indicate the end of the period during which a record is considered valid. It is commonly paired with an accompanying EffectiveFrom field that marks the start of the period. Together, these fields describe a time window during which the data represented by a row is in force, enabling historical tracking of changes over time.

In data modeling, EffectiveTo supports slowly changing dimensions, particularly type 2 scenarios, where previous records are preserved to preserve history while new records capture current values. When an attribute changes, a new row is created with an updated EffectiveFrom and a new EffectiveTo, while the previous row’s EffectiveTo is set to the day before the change. This approach maintains a complete audit trail of how data evolved.

A typical representation uses finite date ranges, with a date value in EffectiveTo indicating a specific end of validity. In many systems, an open-ended or ongoing period is represented by a far-future date such as 9999-12-31 rather than a null value, though conventions may vary. Proper handling avoids overlapping periods and ensures temporal integrity across related records.

Implementation considerations include indexing EffectiveFrom and EffectiveTo to optimize range queries, enforcing constraints to prevent overlapping periods for the same entity, and managing time zones and calendar variations. EffectiveTo is widely used in human resources, pricing catalogs, product configurations, insurance policies, and other domains where historical accuracy and traceability of changes are important. See also EffectiveFrom, validity period, and slowly changing dimensions for related concepts.