In Marketing Cloud - I'm trying to write an SQL that will pull everyone who has opened an email in the last 90 days. I'm getting results from the below SQL, but when I spot-check the data, I'm finding people who are not in All Subscribers. What's going on?
SELECT EmailAddress AS SubscriberKey FROM _subscribers sub
INNER JOIN _sent s ON sub.SubscriberID = s.SubscriberID
INNER JOIN _open o ON o.SubscriberID = sub.SubscriberID
WHERE s.EventDate > DATEADD(day, -90, GETDATE())