mysql - 如何通过日常交易获得不同的用户

Question

我有两个表 User 和 transactions，其中 transaction 表有用户 id

UserID | UserName

TransactionID | UserID | TransactioDate

我需要获取某个时间段内每天进行交易的不同用户的数量，即在特定时间段内每天进行交易的用户数。

我每天都可以获得不同的用户，

SELECT t.TransactioDate, COUNT(DISTINCT u.UserID) 
FROM user u 
INNER JOIN transaction t ON u.UserID = t.UserID AND t.TransactioDate BETWEEN '2018-01-13' AND '2018-02-12' 
GROUP BY CAST(t.TransactioDate AS DATE) 
ORDER BY t.TransactioDate

但我想知道如何在特定时间段内让用户每天都使用 txns。

Answer 1

将它与一个子查询结合起来，该子查询计算每个用户进行交易的不同天数，并返回此计数与该时间段内的天数相同的天数。

SELECT DATE(t.TransactioDate) AS date, COUNT(DISTINCT u.UserID) 
FROM user u 
INNER JOIN transaction t ON u.UserID = t.UserID
INNER JOIN (
    SELECT userID
    FROM transaction
    WHERE TransactioDate BETWEEN '2018-01-13' AND '2018-02-12' 
    GROUP BY userID
    HAVING COUNT(DISTINCT(DATE(transactioDate))) = DATEDIFF('2018-02-12', '2018-01-13') + 1
) AS t1 ON t1.userID = u.userID
WHERE t.TransactioDate BETWEEN '2018-01-13' AND '2018-02-12' 
GROUP BY date
ORDER BY t.TransactioDate