This API allows you to identify users given some anonymous user_id from the Heap SDK and some known identity, such as an email address. When this call is made, all events associated with the provided user_id are migrated to the user with the provided identity.

To protect the integrity of your data, we limit the number of identities mapped to a user_id to 1. We also limit the number of user_ids mapped to an identity to 10, over a one-month period.

As an example, if you send an identify request for user_id 123 and identity susan, we will drop a subsequent identify call for user_id 123 and identity bill. Likewise, if you send 10 identify calls with 10 different user_ids for identity susan in a one-month period, the 11th user_id for identity susan will be ignored.