Q&A for professional and enthusiast programmers
With v0 as( select posts.owneruserid as id from posts where posts.creationdate >= '1/1/2010' and posts.creationdate < '1/1/2011' ), v1 as ( select posts.owneruserid as id from posts where posts.creationdate >= '1/1/2015' and posts.creationdate < '1/1/2016' ), v2 as ( select posts.OwnerUserId as id from posts where posts.OwnerUserId not in (select v0.id from v0) ), v3 as ( select v2.id from v2 where v2.id in (select v1.id from v1) ) select users.displayname from users where users.id in (select id from v3)