I can answer better if you can tell me how do you want to delete them. By Dataset/Batch/Namespace?

Depending on your requirement you can delete them by entire dataset or by a batch or even by individual profiles based on namespace.

Think of an ORG level scenario where Email_ID is marked as identity along with Employee_ID in your schema, now multiple person can upload same DL level Email_ID or shared mailbox id. So if 5 person who put their same DL Email in that case identity activated = 1 whereas there are 5 different profile ...

Hi @irohitshukla    Profiles are qualified audience from your segment but identities are what you defined in your schema. For example, if you've defined both Email & PhoneNo as identity then your ProfileRecieved count is 1 but IdentityActivated count would be 2 for a profile. Now this count will not...

Just to add on to Chetanya's response if cardinality is very low for example your segment logic qualifies 10 audience out of a million then also the estimate may show zero. Because estimation runs on a subset of data and not the full data.

Hi Nikhil,   Little curious on how "Product Viewed Recently (array)" is used in a profile class and not in event.  Can you try the mapper function upsert_array_replace and see if it does the overwrite for you? (If your dataset is upsert enabled) Ref : Data Prep Mapping Functions | Adobe Experience P...

Great initiative. I think a live leaderboard would make it more competitive and interesting.

Profiles were merged as expected. To merge two profiles if any identity matches it'll merge, it doesn't need to be primary identity only.   You can't bypass this because you designed your schema in this way, if you don't want profiles to merge over Email don't mark that as an identity.

Is your lookup schema & dataset profile enabled?