There are several identifier in ActivatePro, depending on the context, but not all of them are unique.
ExternalId
The ExternalId is the unique identifier of a full user in the ActivatePro CDP system. It is technically a user-trait and not mandatory, but can only exist once in the whole system.
This id is used to create and update user per User Management API or User-Feed-Import and should match the id users have in the originating customers database.
If Prediction Models are used as well and the data gets ingested through the Prediction Service first, the ids on both sides have to match.
Often used as ExternalId:
- CustomerId
- Email-Hash
Email and BusinessUnit
The combination of Email and BusinessUnit can also only exist once in the system.
The Email alone is not unique and can exist multiple times with different BusinessUnits. The only way an Email would be unique is when the customer does not use BusinessUnits, for which the system uses the internal "default".
Updates to a user without an ExternalId but with an Email can be made with the "Leads"-Endpoint of the UIser Management API.
xngGlobalUserId
This id, also sometimes referred to as "xngId", is the internal unique identifier of any user in the ActivatePro CDP system. It is visible in every user profile and is also saved in the tracking cookie, if web-tracking is implemented.
This id is not used to import/update users (with the exception of deleting users).
MobileId
The MobileId is used with Mobile Tracking, e.g. with an App. Once connected to a user its not necessary to know any of the other ids/unique idendifier, as long as the Mobile Tracking API is used.
This id can only be active in one user, but each user can have multiple MobileIds (e.g. for different apps, devices etc.).