我有一个悬而未决的请求,要为我编写的温度日志应用程序编写一个报告,但我似乎无法确定该查询。
应用程序存储温度日志。这些日志每天要在几个不同的地方做3次。每个日志包含一个或多个区域,其中包含一个或多个设备。
我的报告需要显示设备(EquipmentStoreID),在给定的报告日期范围内,设备(EquipmentStoreID)连续出现超过3个记录周期的不良温度。我需要显示“岛”,或者坏天气开始和结束的日期范围。一些注意事项:
如果错过一个时间段,就应该认为是一个坏温度。但是,失败的temps的“孤岛”不应该从丢失的日志开始。
在给定的时间段内,同一个位置可以完成多个日志,在这种情况下,好的temp将胜过坏的temp。
这是我的SQLFiddle。我的结果是不正确的,因为连续的失败开始于一个实际错过的时间段,并且我无法找出如何处理同一时间段的多个日志。
非常感谢您的帮助!
最佳答案
这是我想到的。
为了避免在丢失的日志上启动孤岛,我将该行的日期与我们在每个存储中看到的第一个记录日期(下面查询中的minlog)进行了比较。如果行的日期早于第一个日志日期,那么我们知道它发生在开始录制之前,并且我不会用错误标志来标记它。
为了处理同一时间段内的多个日志,我在stagedrows中添加了一个priority字段,我们可以使用它来获取每个store/datetime的第一个条目,从而对成功的日志进行优先级排序。
WITH TargetLogs
AS (SELECT le.*,
CONVERT(DATETIME, CONVERT(DATE, lh.StartDateTime)) as Date,
lh.TimePeriodID,
lh.StartDateTime
FROM [dbo].[LogEquipment] le
JOIN [dbo].[LogArea] la
ON le.LogAreaID = la.LogAreaID
JOIN [dbo].[LogHeader] lh
ON lh.LogHeaderID = la.LogHeaderID
WHERE lh.StartDateTime Between CAST('2015-01-14' AS DateTime)
AND CAST('2015-01-16' AS DateTime)
),
Dates --Generate date range
AS (SELECT CAST('2015-01-14' AS DateTime) 'date'
UNION ALL
SELECT Dateadd(dd, 1, t.date)
FROM Dates t
WHERE Dateadd(dd, 1, t.date) <= CAST('2015-01-16' AS DateTime)),
DesiredDatesAndTimePeriods --Generate datetimes for all timeperiods between date range
AS (SELECT DISTINCT tp.TimePeriodID,
tp.TimeDescription,
tp.StartTime,
d.Date,
d.Date + CONVERT(DATETIME, tp.StartTime) AS LogStartDateTime,
le.EquipmentStoreID
FROM dbo.TimePeriod tp
CROSS JOIN Dates d
CROSS JOIN LogEquipment le
WHERE tp.IsActive = 1),
StagedRows
AS (SELECT * FROM
(
SELECT d.LogStartDateTime,
d.EquipmentStoreID,
t.LogEquipmentID,
t.CorrectiveAction,
CASE WHEN minlog.MinStartDateTime <= d.LogStartDateTime
AND (t.LogEquipmentID IS NULL OR CorrectiveAction IS NOT NULL)
THEN 1 ELSE 0 END AS FailedFlag,
ROW_NUMBER() OVER (PARTITION BY d.Date, d.TimePeriodID
ORDER BY CASE WHEN CorrectiveAction IS NULL THEN 0 ELSE 1 END)
AS Priority
FROM DesiredDatesAndTimePeriods d
LEFT OUTER JOIN TargetLogs t
on d.Date = t.Date AND d.TimePeriodId = t.TimePeriodId
LEFT OUTER JOIN (SELECT EquipmentStoreId, MIN(StartDateTime) as MinStartDateTime FROM TargetLogs GROUP BY EquipmentStoreId) minlog
on d.EquipmentStoreID = minlog.EquipmentStoreID
) dt WHERE Priority = 1)
SELECT EquipmentStoreID,
Count(*) AS ConsecutiveFails,
Start_date = Min(LogStartDateTime),
Stop_date = Max(LogStartDateTime)
FROM (SELECT EquipmentStoreID,
FailedFlag,
LogStartDateTime,
ROW_NUMBER()
OVER (
ORDER BY EquipmentStoreID, LogStartDateTime) - ROW_NUMBER()
OVER (
PARTITION BY EquipmentStoreID, FailedFlag
ORDER BY EquipmentStoreID, LogStartDateTime)
grp
FROM StagedRows) A
GROUP BY EquipmentStoreID, FailedFlag,
grp
HAVING FailedFlag = 1
AND Count(*) > 3
ORDER BY Min(LogStartDateTime)
关于sql - 卡在涉及时间段的空白和离岛查询上,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/27992749/