MySQL如何找到具有不同创建日期的不同客户端的平均/天

我尝试了以下查询，但不幸的是它们不起作用：（。 值得一提的是，每个客户都有多个CustomerUsers

select (a.TotalJobs / b.DaysActive) from
(select count(jr.id) as TotalJobs
from jobrequests jr, customers c, customerusers cu
where jr.customeruserid=cu.id
and cu.customerid=c.id
group by c.name) as a,
(select datediff(curdate(), from_unixtime(c.CreationTime)) as DaysActive
from customers c
group by c.name)  as b

请看下面的表格

Jobs: +----+--------------+ | ID | JobRequestID | +----+--------------+ | 1 | 1 | | 2 | 1 | | 3 | 1 | | 4 | 1 | | 5 | 1 | | 6 | 2 | | 7 | 2 | | 8 | 3 | | 9 | 3 | | 10 | 3 | | 11 | 4 | | 12 | 4 | | 13 | 5 | | 14 | 5 | | 15 | 6 | | 16 | 7 | | 17 | 8 | | 18 | 8 | | 19 | 9 | | 20 | 10 | +----+--------------+ JobRequests: +----+---------------+ | ID | CustomeUserID | +----+---------------+ | 1 | 1 | | 2 | 1 | | 3 | 2 | | 4 | 2 | | 5 | 2 | | 6 | 3 | | 7 | 4 | | 8 | 4 | | 9 | 4 | | 10 | 5 | | 11 | 5 | | 12 | 5 | | 13 | 6 | | 14 | 6 | | 15 | 7 | +----+---------------+ CustomerUsers: +----+------------+ | ID | CustomerID | +----+------------+ | 1 | 1 | | 2 | 1 | | 3 | 1 | | 4 | 2 | | 5 | 2 | | 6 | 2 | | 7 | 2 | | 8 | 3 | | 9 | 3 | | 10 | 4 | +----+------------+ Customers: +----+------+--------------+ | ID | Name | CreationTime | +----+------+--------------+ | 1 | a | 1415814194 | | 2 | b | 1415814194 | | 3 | c | 1415986994 | | 4 | d | 1415986994 | +----+------+--------------+ 工作： +----+--------------+ |ID |作业请求ID| +----+--------------+ | 1 | 1 | | 2 | 1 | | 3 | 1 | | 4 | 1 | | 5 | 1 | | 6 | 2 | | 7 | 2 | | 8 | 3 | | 9 | 3 | | 10 | 3 | | 11 | 4 | | 12 | 4 | | 13 | 5 | | 14 | 5 | | 15 | 6 | | 16 | 7 | | 17 | 8 | | 18 | 8 | | 19 | 9 | | 20 | 10 | +----+--------------+ 职位申请： +----+---------------+ |ID |客户服务ID| +----+---------------+ | 1 | 1 | | 2 | 1 | | 3 | 2 | | 4 | 2 | | 5 | 2 | | 6 | 3 | | 7 | 4 | | 8 | 4 | | 9 | 4 | | 10 | 5 | | 11 | 5 | | 12 | 5 | | 13 | 6 | | 14 | 6 | | 15 | 7 | +----+---------------+ 客户： +----+------------+ |ID |客户ID| +----+------------+ | 1 | 1 | | 2 | 1 | | 3 | 1 | | 4 | 2 | | 5 | 2 | | 6 | 2 | | 7 | 2 | | 8 | 3 | | 9 | 3 | | 10 | 4 | +----+------------+ 客户： +----+------+--------------+ |ID |名称|创建时间| +----+------+--------------+ |1 | a | 1415814194| |2 | b | 1415814194| |3 | c | 1415986994| |4 | d | 1415986994| +----+------+--------------+ 目前，它返回16个结果（4X4），将第一个子查询中的每个结果除以第二个子查询中的每个结果（每个子查询返回4个结果）。是否有人能帮助我将此结果从子查询1中仅除以一个结果，再除以子查询2的共同响应

---

提前谢谢。

我猜您需要将您的结果结合在一起--

尝试这样的操作，将

c.id

添加到每个子查询中（最好按它分组，而不是按名称分组）：

---

请注意，我已更新了您的语法，以使用更标准的

join

语法。

我怀疑您可以按照您的要求执行以下查询：

select c.name, count(*) / (datediff(curdate(), from_unixtime(c.CreationTime))
from customerusers cu join
     jobrequests jr
     on jr.customeruserid = cu.id join
     customers c 
     on cu.customerid = c.id
group by c.name;

---

我不明白你为什么需要两个子查询来完成这个任务。

你能描述一下你想要完成什么吗？+1，我不想花那么多脑力，但我完全同意，这是一个更好的解决方案。。。

select c.name, count(*) / (datediff(curdate(), from_unixtime(c.CreationTime))
from customerusers cu join
     jobrequests jr
     on jr.customeruserid = cu.id join
     customers c 
     on cu.customerid = c.id
group by c.name;