如何在MySQL中计算每周唯一访问次数

Question

我在MySQL中有此查询来检查对系统的唯一访问：

SELECT COUNT(DISTINCT id_user) AS total, access_day FROM access WHERE (access_day BETWEEN '2018-01-21' AND '2019-01-21') GROUP BY access_day

有效！

客户要求检查其系统的每周唯一访问权限，如果用户在1周内至少访问过一次，则已经告诉他访问权限，该怎么办？我尝试过这种方式，但是数字有误：

SELECT COUNT(DISTINCT id_user) AS total, access_day FROM access WHERE (access_day BETWEEN '2018-01-21' AND '2019-01-21') GROUP BY WEEK(access_day)

Answer 1

您尝试过吗？

示例：

SELECT FROM_DAYS(TO_DAYS(sales_time) -MOD(TO_DAYS(sales_time) -1, 7)) AS week_beginning,
       SUM(gross) AS total,
       COUNT(*) AS transactions
FROM sales
GROUP BY FROM_DAYS(TO_DAYS(sales_time) -MOD(TO_DAYS(sales_time) -1, 7))
ORDER BY FROM_DAYS(TO_DAYS(sales_time) -MOD(TO_DAYS(sales_time) -1, 7))

并且，如果您的业务规则说您的工作周从星期一开始，请将-1更改为-2。