1. An article comprising one or more machine-readable media storing instructions operable to cause one or more machines to perform operations, the operations comprising: receiving, from a data processing system, a collection of mapping information identifying a first object and a first collection of two or more keys used to identify the first object; determining whether a first key in the first collection is found in a first mapping group of a mapping data store; determining whether second key in the first collection is found in a second mapping group of the mapping data store; and merging the first mapping group and the second mapping group to reflect that objects from the first mapping group and the second mapping group are related.