Q&A for people studying math at any level and professionals in related fields
WITH TempTable AS ( SELECT OwnerUserId, COUNT(CASE WHEN CreationDate BETWEEN '2022-09-04' AND '2022-11-27' THEN Id END) AS CountPeriodA, COUNT(CASE WHEN CreationDate BETWEEN '2022-12-04' AND '2023-02-26' THEN Id END) AS CountPeriodB FROM posts WHERE PostTypeId = 1 GROUP BY OwnerUserId HAVING COUNT(CASE WHEN CreationDate BETWEEN '2022-09-04' AND '2022-11-27' THEN Id END) >= 1 AND COUNT(CASE WHEN CreationDate BETWEEN '2022-12-04' AND '2023-02-26' THEN Id END) >= 1 ), UserQuestions AS ( SELECT p.OwnerUserId, p.Id AS QuestionId, p.CreationDate AS QuestionCreationDate FROM posts p INNER JOIN TempTable tt ON p.OwnerUserId = tt.OwnerUserId WHERE p.PostTypeId = 1 ), FirstAnswer AS ( SELECT a.ParentId AS QuestionId, a.CreationDate AS FirstAnswerCreationDate, ROW_NUMBER() OVER (PARTITION BY a.ParentId ORDER BY a.CreationDate) AS AnswerRank FROM posts a WHERE a.PostTypeId = 2 AND a.CreationDate BETWEEN '2022-09-04' AND '2023-02-26' ), FINAL AS ( SELECT ROW_NUMBER() OVER (ORDER BY uq.OwnerUserId DESC) AS IndexColumn, uq.OwnerUserId, uq.QuestionId, uq.QuestionCreationDate, fa.FirstAnswerCreationDate FROM UserQuestions uq LEFT JOIN FirstAnswer fa ON uq.QuestionId = fa.QuestionId WHERE fa.AnswerRank = 1 ) SELECT top 5 * FROM FINAL order by IndexColumn desc