mysql:统计子表中的记录,按日期分组
我有两个表,一个包含任务的表和一个存储任务进度的表“Tasklog”mysql:统计子表中的记录,按日期分组,mysql,Mysql,我有两个表,一个包含任务的表和一个存储任务进度的表“Tasklog” Tasks ID Description 1 task1 2 task2 3 task3 4 task4 5 task5 任务日志 ID taskId dtTime Status 1 1 2016-01-01 new 2 1 2016-02-10 in progress 3 1 2016-03-03 closed 4 2 2016
Tasks
ID Description
1 task1
2 task2
3 task3
4 task4
5 task5
任务日志
ID taskId dtTime Status
1 1 2016-01-01 new
2 1 2016-02-10 in progress
3 1 2016-03-03 closed
4 2 2016-01-01 new
5 2 2016-01-10 in progress
6 2 2016-01-11 closed
7 3 2016-01-01 new
8 4 2016-01-01 new
9 5 2016-01-01 new
10 5 2016-01-01 in progress
一个任务可以有多个任务日志记录
现在,我想创建一个报告,显示在过去24个月中,每月有多少个任务处于“打开”状态(打开意味着在该月没有状态为“关闭”的tasklog记录)
所以我需要这样的东西:
2016-01 4
2016-02 4
2016-03 3
我相信这些应该是查询结果的实际数字
我正在努力写一个合适的查询来实现这一点。我想我很接近了,但是通过下面的查询,我正在计算tasklog记录,相反,我希望计算任务记录,而不管它们有多少tasklog记录
select month(dtTime) month, year(dtTime) year, count(t.id) as number
from tasklog tl
join tasks t on t.id = taskId
where dtTime > DATE_ADD(now(), INTERVAL -2 YEAR)
and t.id not in (
select id from tasklog tl1
where status in ('closed')
and month(tl1.dtTime) = month(tl.dtTime)
and year(tl1.dtTime) = year(tl.dtTime)
)
group by month(dtTime), year(dtTime)
order by dtTime;
有什么建议我可以最好地做到这一点吗
创建/填写表格的代码:
CREATE TABLE tasks
(`id` int, `description` varchar(5))
;
INSERT INTO tasks
(`id`, `description`)
VALUES
(1, 'task1'),
(2, 'task2'),
(3, 'task3'),
(4, 'task4'),
(5, 'task5')
;
CREATE TABLE tasklog
(`ID` int, `taskId` int, `dtTime` datetime, `Status` varchar(11))
;
INSERT INTO tasklog
(`ID`, `taskId`, `dtTime`, `Status`)
VALUES
(1, 1, '2016-01-01 00:00:00', 'new'),
(2, 1, '2016-02-10 00:00:00', 'in progress'),
(3, 1, '2016-03-03 00:00:00', 'closed'),
(4, 2, '2016-01-01 00:00:00', 'new'),
(5, 2, '2016-01-10 00:00:00', 'in progress'),
(6, 2, '2016-01-11 00:00:00', 'closed'),
(7, 3, '2016-01-01 00:00:00', 'new'),
(8, 4, '2016-01-01 00:00:00', 'new'),
(9, 5, '2016-01-01 00:00:00', 'new'),
(10, 5, '2016-01-01 00:00:00', 'in progress')
;
针对Stefano Zanini的更新
似乎这两种解决方案都没有得到正确的结果。我认为,正确的结果是:
2016-01 4
2016-02 4
2016-03 3
你的询问只给了我:
1 2016 4
如果我将distinct添加到查询中,我会得到:
1 2016 5
2 2016 1
3 2016 1
我会选择左路
select month(tl.dtTime) month, year(tl.dtTime) year, count(t.id) as number
from tasks t
join tasklog tl
on t.id = tl.taskId and tl.status = 'new'
left join tasklog tl2
on t.id = tl2.taskId and month(tl.dtTime) = month(tl2.dtTime) and tl2.status = 'closed'
where dtTime > DATE_ADD(now(), INTERVAL -2 YEAR)
and tl2.taskId is null
group by month(tl.dtTime), year(tl.dtTime)
order by dtTime;
编辑
…但您可能只需要在计数中添加distinct
子句
count(distinct t.id)
进一步解释后编辑
我误解了这个要求。这将实现以下目的:
select distinct mm.month, count(distinct tl.taskId)
from (select distinct month(dtTime) mm from tasklog) mm
join tasklog tl
on mm.montId >= month(tl.dtTime) and tl.Status = 'new'
left join
tasklog tl2
on mm.month >= month(tl2.dtTime) and tl2.Status = 'closed' and tl.taskId = tl2.taskId
where tl2.taskId is null
group by mm.month
order by 1;
第一个join会在每个月加入到该月为止打开的所有任务。对于第二个联接(左侧联接),如果任务在该月或更早的一个月内关闭,则为每个月/taskId指定一个值。从这里,您可以只筛选每个月打开的任务,筛选不具有此值的行
您将不得不添加年份,也许还需要优化连接子句,但是使用您提供的示例数据,这个查询非常好。这就是我的结论:
select distinct mm.year as year,
mm.month as month,
count(distinct tl.taskId) number
from (select distinct month(dtTime) month , year(dttime) year from tasklog) mm
join tasklog tl
on mm.month >= month(tl.dtTime) and mm.year >= year(tl.dtTime) and tl.Status !='closed'
left join
tasklog tl2
on mm.month >= month(tl2.dtTime) and mm.year >= year(tl2.dtTime) and tl2.Status = 'closed' and tl.taskId = tl2.taskId
where tl2.taskId is null
group by mm.month
order by 1;
请看我在问题中的回答(请大耳朵评论)对不起,我误解了您的要求。我用一个解决方案编辑了我的答案,这个解决方案应该正是你所需要的。谢谢Stefano,这个查询确实给了我想要的结果,我花了一段时间才弄清楚发生了什么,但现在我明白了。这似乎是一个聪明的解决方案,谢谢!