查找结束日期和开始日期在同一个月的订阅者数量

Question

我想获取在过去 12 个月内终止原因为“xxx”的同一个月内终止和重新注册的订阅者的数量。

在上述示例中，订阅者“1245”因“xxx”原因被终止，但在同一个月重新注册。我想统计过去 n 个月中这种情况每月发生的次数。

我尝试了下面的代码来获取 PersonID，但在一个月内无法获取计数。

SELECT DISTINCT PersonID FROM Membership A

INNER JOIN (SELECT StartYrMo FROM Membership) B

ON A.EndYrMo = B.StartYrMo

WHERE A.TermReason = 'xxx'

ORDER BY PersonID

编辑还有更多内容。我想要所有连续至少 6 个月这样做的 PersonId。含义：人“A”在 201901 年因“xxx”原因被终止。“A”在 201902 年至 201908 年因同样的“xxx”原因再次终止，至少 6 个月。我想要所有这样做的人的 ID。

Answer 1

应该这样做：

SELECT DISTINCT A.PersonID FROM Membership A

INNER JOIN Membership B ON A.PersonID = B.PersonID
INNER JOIN Membership C ON A.PersonID = C.PersonID
INNER JOIN Membership D ON A.PersonID = D.PersonID

WHERE A.TermReason = 'xxx'
AND   B.TermReason = 'xxx'
AND   C.TermReason = 'xxx'
AND   D.TermReason = 'xxx'

AND   B.StartMonth = A.EndMonth
-- following assumes minimum date in your dataset is '201101'.
-- '+ 89' returns '201201' instead of '201113' when EndMonth is '201112'.
AND   C.StartMonth = CASE WHEN A.EndMonth IN ('201112', '201212', '201312', '201412', '201512', '201612', '201712', '201812', '201912')
                     THEN A.EndMonth + 89 ELSE A.EndMonth + 1 END
AND   D.StartMonth = CASE WHEN A.EndMonth IN ('201112', '201212', '201312', '201412', '201512', '201612', '201712', '201812', '201912', '201111', '201211', '201311', '201411', '201511', '201611', '201711', '201811', '201911')
                     THEN A.EndMonth + 90 ELSE A.EndMonth + 2 END
-- repeat for additional months as needed.

ORDER BY PersonID

为减少冗余，此代码仅查看连续 3 个月。如果它没有返回任何结果，那么您不必担心为其他月份编写额外的代码行（如果它是一次性请求）。因为如果连续3个月没有人，那么连续6个月也没有人。我希望这会有所帮助:)

Answer 2

要获得重新订阅的人：

select m2.PersonID, m2.StartMonth as ResubscriptionMonth
            from Membership m1 inner join Membership m2
            on m1.PersonID = m2.PersonID
            where m1.TermReason = 'xxx' and m1.EndMonth = m2.StartMonth

按月获取数字：

select Resubscibtions.ResubscriptionMonth, Count(*)
from (
        select m2.PersonID, m2.StartMonth as ResubscriptionMonth
        from Membership m1 inner join Membership m2
        on m1.PersonID = m2.PersonID
        where m1.TermReason = 'xxx' and m1.EndMonth = m2.StartMonth) as Resubscibtions 
group by Resubscibtions.ResubscriptionMonth