Firebase Analytics - Add custom keys in device_Info or geo_info

Question

I have been using Firebase Analytics for quite some time now and I wanted to know if we could add or modify some specific keys (other than userId) in the analytics data visible on BigQuery? The reason I'm asking this is so I can map my old users to the new users on Firebase.

Looking at the analytics data on BigQuery, inside device_info there is a key device_id whose value I always found null. I want to modify this value as I was previously setting it for my old users. This would help migrate users from my old analytics db to Firebase. Not only the device_info, can I modify/add new key-value params in the other dimensions too?

All help is appreciated.

Answer 1

device_id in device_info is only populated on iOS platform with the IDFV, if IDFA is not available. It is not used for the Android platform.

https://support.google.com/firebase/answer/7029846?hl=en

There is no support for overriding these values that I'm aware of.

Meanwhile, if you have access to, say, the resettable_device_id, you might be able to use that to join in other data you have for the old users in BigQuery.