As described in the refineConfig section, Oracle ATG Web Commerce Search can calculate refinements based on the query results, in order to offer the end-user a quick way of narrowing the search.

The key value is a value of the refineConfigMapProp property to try to use first to pre-empt the determination of a value from the search results. For example, if the property is ancestorCategories.repositoryId, the key value should be a valid value of this property, such as cat1009.

<query refineConfig="$map" refineConfigDefault="default"
refineConfigMapProp="ancestorCategories.repositoryId"
refineConfigMapKey="cat1009"