如果数据不存在，则时隙返回零

Question

我正在尝试每分钟获取两分钟的数据，对于 mid、sid、pid 组合，每秒应该有数据。如果每个组合的数据在一秒钟内不存在，则应将 IC 值返回为零。两分钟内，如果任何时隙的 mid、sid、pid 组合不存在数据，则将有 120 个时隙，则应返回零。这data 用于绘制折线图，​​如果数据不存在，则应归零。

CREATE TABLE [dbo].[DeviceData](
[Id] [BIGINT] IDENTITY(1,1) NOT NULL,
[MId] [INT] NOT NULL,
[SId] [INT] NOT NULL,
[PId] [INT] NOT NULL,
[DataTime] [DATETIME] NOT NULL,
[IC] [INT] NOT NULL,
CONSTRAINT [PK_DeviceData] PRIMARY KEY CLUSTERED 
(
[Id] ASC
)

 SELECT  [MId] ,
    [SId] ,
    [PId] ,
    [DataTime] ,
    SUM([IC]) AS Value
 FROM    [DeviceData]
 WHERE   DataTime BETWEEN DATEADD(MINUTE, -2, GETUTCDATE())
             AND     GETUTCDATE()
 GROUP BY [MId] ,
    SID ,
    PId ,
    [DataTime];

Answer 1

你需要一个数字 CTE：

with Numbers as
(
select 1 as NN
union all
select NN+1
from Numbers
where NN < 120
)
, Times as
(
select dateadd(ss, 
               NN, 
               DATEADD(MINUTE, 
                       -2, 
                       dateadd(ms, 
                               -datepart(ms, 
                                        GETUTCDATE()),
                               GETUTCDATE()) ) as Timeslot
from Numbers
)
select Timeslot, DD.*
from Times
left join DeviceData DD
  on Timeslot = dateadd(ms, -datepart(ms, GETUTCDATE()),GETUTCDATE())
OPTION (MAXRECURSION 1000) -- This will bypass the recursion error