计数天凡记录未记录SQL

Question

我想写一个查询，执行以下操作：

• 组的结果由'key'列
• 和的次数的'device id'没有记录'data'

这是样本数据

。

最终的输出应该是这样的：

| Key | Count of Missed Data | 
| 14 |   123   | 
| 124 |   356   | 

哪里count of missed data是一个'device id'没有在最近365天记录'data'天数。

**注意：每'key'可能有500 'device id'。每次在这一年的某个日历日，这些设备中的一个设备不会记录'data'，并计算按键分组的“错过的数据”点的总数。

请询问您是否有任何问题。谢谢您的帮助！

约翰

每下面的建议，这是我现在运行的代码。批评？

Select 
a.descr AS 'Community', 
a.meter_type AS 'Meter Type', 
sum(a.misseddaysperdevice) as [Count of Missed Days] 
From 
    (
    Select 
     fmr.subdivisionkey, 
     sub.descr, 
     meter_type, 
     365-count(distinct(convert(varchar, fmr.read_date, 112))) as misseddaysperdevice 
    From 
     FactMeterRead fmr 
     INNER JOIN DimSubdivision sub on sub.subdivisionkey = fmr.subdivisionkey 
    Where 
     fmr.read_date > getdate()-364 
    Group By 
     fmr.SubdivisionKey, sub.descr, fmr.meter_num, meter_type 
    ) a 
Group By 
    a.descr, meter_type 
Order By 
    [Count of Missed Days] DESC 

Answer 1

像这样的东西应该这样做：

select key, 365 - count(distinct(cast(date as date))) as [Count of Missed Data] 
from MyTable 
where date > getdate() - 365 
group by key 

编辑：总结的漏天计数所有设备对于给定的关键，试试这个：

select key, sum(MissedDaysPerDevice) as [Count of Missed Data] 
from (
    select key, 365 - count(distinct(cast(date as date))) as MissedDaysPerDevice 
    from MyTable 
    where date > getdate() - 365 
    group by key, device 
) a 
group by key 

Answer 2

好，错过的天数是365天的天数。这是比较容易计算的，因此：

select key, count(distinct cast(date as date)) as days_present, 
     365 - count(distinct cast(date as date)) as days_absent 
from t 
where date >= dateadd(day, -364, cast(getdate() as date)) 
group by key; 

Answer 3

我不喜欢硬编码365天....问题的时间的1/4 ......

  declare @asOfDate date = getdate() 
     declare @start date 
     set @start = dateadd(year, -1, @asOfDate) 

     select sumDevice.[Key], sum(sumDevice.MissingDaysCount) as MissingDaysCount 
     from ( 
      select mt.[Key], 
      mt.[device id], 
      datediff(day, @start, @asOfDate) - isnull(count(distinct cast(mt.[Date] as date)), 0) 
              as [MissingDaysCount] 
      from myTable mt 
      where mt.[date] between @start and dateadd(day, 1, @asOfDate) 
      group by mt.[key], 
        mt.[device id]) as SummaryKey 
     group by sumDevice.[Key] 
     order by sumDevice.[Key]