Survivorship rules determine the outcome of merging two records by declaring which values survive for each attribute, reference, and data container on the golden record. The application of survivorship differs slightly across match actions, but the overall principles remain the same. When merging records, the surviving attribute values are selected by survivorship rules.
When merging two existing golden records – which can happen when updating information on one record results in both records being the same real-world object – one of the records must survive and the other must be deactivated. The default is to allow the record with the oldest STEP revision to persist and to deactivate the youngest record. This behavior can be overridden as defined in the Creating a Merge Keep First Handler topic here.
When selecting which values survive, the basic strategy is often to either trust some sources more than other sources or to preserve the most recent updates. These kinds of rules are called Most Recent and Trusted Source. A set of general rules can be configured, but if special business logic is required, a business action survivorship rule can be implemented to apply surviving values to golden records.
Survivorship rules are defined independently for an object's name, references, data containers, and attributes / attribute groups. It is possible to apply different survivorship rules to groups of attributes or attributes and references individually, so that, for example, the value of one attribute follows a 'trusted source' rule while the value of other attributes follow a 'most recent' rule.
For more information, refer to the following topics: