To answer your questions about distinct_ids in Mixpanel:
1. Yes, you can fetch all distinct_ids associated with a profile through the Mixpanel API. The Engage API allows you to query user profile data, including distinct_ids. According to the Query API documentation, you can use the /engage endpoint to query profiles.
2. Regarding your second question about getting the same distinct_id you're passing in the /api/query/engage API:
The behavior you're observing is likely due to Mixpanel's identity management system. When you query using a distinct_id, Mixpanel may return a different distinct_id if it has been merged with another identity.
According to the Identity Management Overview, Mixpanel uses an ID merge system to connect multiple identifiers to a single user. This means that even if you query with one distinct_id, you might receive a different one in the response if Mixpanel has determined they belong to the same user.
To get the exact distinct_id you're passing, you can try using the output_properties parameter in your API request to specifically request the distinct_id property. However, keep in mind that Mixpanel may still return the canonical distinct_id for that user, which might be different from the one you passed.
If you need to maintain a mapping between the distinct_ids you're passing and the ones Mixpanel is using, you might need to implement this on your side or use additional Mixpanel features like the identity mapping table, which is available for certain types of data exports as mentioned in the User Identity Resolution documentation.
For the most accurate and up-to-date information on handling distinct_ids and identity management in Mixpanel, I recommend consulting the official Mixpanel documentation or contacting Mixpanel support directly.
