A system unique identifier. Specifically, in aggregation systems, the Key is the system unique identifier from the system that the record was just retrieved. This may be identical to the related xxxId identifier, but the key is guaranteed unique for this record set. This is a foreign key relating to the Member resource's MemberKey. This is the numeric only key and used as an alternative to the CoListAgentKey field.
Page Revision Date: Aug 09 2017