Properties are defined by multiple settings, ranging from an "accessor" that tells Firstparty how to retrieve the data to multiple flags that define how to maintain privacy of the data both in-use and when "forgotten" due to a customer request or other business need.
Accessor Properties store a simple key-value pair in the database on the defined Item, and it simply returns the value stored at the key defined by the accessor. This might be a
first_name on a Profile, or a
page_category on an Event.
Identifying Properties are just Accessor Properties with a bit more magic - they may be used to reconcile Profiles by defining a unique, identifying key that is found on an Item. These are typically things like an
Firstparty will automatically merge and resolve two or more Profiles when an Identifying Property is received that matches multiple Profiles.
When two Profiles are merged, the same Property may have a defined value on each Profile. Individual Properties may be configured to use the value from either the oldest or newest Profile.