Q&A for those who study, teach, research and apply economics and econometrics
WITH TempTable AS ( SELECT OwnerUserId, COUNT(CASE WHEN CreationDate BETWEEN '2019-09-01' AND '2019-11-24' THEN Id ELSE NULL END) AS CountPeriodA, COUNT(CASE WHEN CreationDate BETWEEN '2019-12-01' AND '2020-02-23' THEN Id ELSE NULL END) AS CountPeriodB FROM posts WHERE PostTypeId = 1 GROUP BY OwnerUserId HAVING COUNT(CASE WHEN CreationDate BETWEEN '2019-09-01' AND '2019-11-24' THEN Id ELSE NULL END) >= 1 AND COUNT(CASE WHEN CreationDate BETWEEN '2019-12-01' AND '2020-02-23' THEN Id ELSE NULL END) >= 1 ), FINAL As( SELECT ROW_NUMBER() OVER (ORDER BY posts.OwnerUserId DESC) AS IndexColumn, posts.OwnerUserId, posts.Id, posts.CreationDate, posts.body FROM posts INNER JOIN TempTable ON posts.OwnerUserId = TempTable.OwnerUserId WHERE PostTypeId=1 AND CreationDate between '2019-09-01' AND '2020-02-23' GROUP BY posts.OwnerUserId,posts.Id, posts.CreationDate,posts.body,posts.tags ) Select top 5 * From FINAL order by Indexcolumn desc