EF Core 3.1 OrderByDescending 好奇 T-SQL 翻译
EF Core 3.1 OrderByDescending curious T-SQL translation
我有以下 Linq 查询，它们仅在 where 子句上有所不同：
查询 1：
var initialList = await
context.AlertDetailsDbSet
// Pouring the TrackedVehicule related graph
.Include(ad => ad.TrackedVehicule.Registration)
.Include(ad => ad.TrackedVehicule.Device)
.Include(ad => ad.TrackedVehicule.GpsBox.Icon)
.Include(ad => ad.TrackedVehicule.GpsBoxTypeNavigation.Icon)
.Include(ad => ad.TrackedVehicule.VehiculeGpsBoxInfo.VehiculeConfigurationNavigation)
// Loading the associated alert
.Include(ad => ad.Alert)
#if NETSTANDARD2_1
// This filter is not supported with EF Core 2.X
// It should be done client side
.Where(ad => ad.Alert.CompanyId == companyId && ad.Alert.AlertRule.Contains("SerializableContextAlert") && ad.AlertDateTime >= startDate && ad.AlertDateTime <= endDate && ad.TrackedVehicule != null && ad.TrackedVehicule.CompanyId == companyId && ad.TrackedVehicule.RowEnabled == true && (ad.TrackedVehicule.GpsBoxType == 29 || ad.TrackedVehicule.GpsBoxType == 12))
#endif
.Skip(0)
// A limit is applied on returned elements
.Take(1000)
.OrderByDescending(ad => ad.AlertDateTime)
// .Skip(skip)
// .Take(take)
// We disable the tracking mechanism because the context will be thrown away as soon as we have the data
.AsNoTracking()
// We want an asynchrounous execution
.ToListAsync(cancellationToken)
查询 2：
var initialList = await
context.AlertDetailsDbSet
// Pouring the TrackedVehicule related graph
.Include(ad => ad.TrackedVehicule.Registration)
.Include(ad => ad.TrackedVehicule.Device)
.Include(ad => ad.TrackedVehicule.GpsBox.Icon)
.Include(ad => ad.TrackedVehicule.GpsBoxTypeNavigation.Icon)
.Include(ad => ad.TrackedVehicule.VehiculeGpsBoxInfo.VehiculeConfigurationNavigation)
// Loading the associated alert
.Include(ad => ad.Alert)
#if NETSTANDARD2_1
// This filter is not supported with EF Core 2.X
// It should be done client side
.Where(ad => ad.Alert.CompanyId == companyId && ad.Alert.AlertRule.Contains("SerializableContextAlert") && ad.TrackedVehicule != null && ad.TrackedVehicule.RowEnabled == true && ad.TrackedVehicule.CompanyId == companyId && (ad.TrackedVehicule.GpsBoxType == 29 || ad.TrackedVehicule.GpsBoxType == 12) && ad.AckTime.HasValue == acknwoledged)
#endif
.OrderByDescending(ad => ad.AlertDateTime)
.Skip(skip)
.Take(take)
// We disable the tracking mechanism because the context will be thrown away as soon as we have the data
.AsNoTracking()
// We want an asynchrounous execution
.ToListAsync(cancellationToken)
基本上，第一个查询是（除其他事项外）过滤布尔值 属性，而第二个查询是 过滤范围日期.
我的问题是这些查询未转换为导致不同结果的相同 T-TSQL。
TSQL 1 :
exec sp_executesql N'SELECT [t].[AlertDetailID], [t].[AckMachineName], [t].[AckPhoneNumber], [t].[AckTime], [t].[AckUserName], [t].[AlertDateTime], [t].[AlertID], [t].[AlertedCorridorId], [t].[AlertedItemId],
[t].[AssociatedVehiculeID], [t].[AssociatedVehiculeUserID], [t].[Context], [t].[CustomID], [t].[CustomInfo], [t].[DbInsertTime], [t].[IsFleetAlert], [t].[MessageStatus], [t].[ReceivedTime], [t].[RowVersion],
[t].[SafeProtectCustomInfo], [t].[TrackedVehiculeID], [t].[TrackedVehiculeUserID], [v0].[VehiculeID], [v0].[Address], [v0].[AddressProtocol], [v0].[BoardID], [v0].[Category], [v0].[CompanyID], [v0].[CustomId], [v0].[DbInsertTime], [v0].[Description], [v0].[GpsBoxSubType], [v0].[GpsBoxTrackingDelay], [v0].[GpsBoxType], [v0].[HardwareID], [v0].[HasGeoWorker], [v0].[IconID], [v0].[Name], [v0].[PhoneNumber], [v0].[RowEnabled], [v0].[RowVersion], [v0].[VehiculeUserID], [r].[VehiculeID], [r].[CompanyId], [r].[LatestRegistrationStatusChangeDate], [r].[RegistrationMailSent], [r].[RegistrationStatusId], [d].[VehiculeID], [d].[AppVersion], [d].[Brand], [d].[Details], [d].[Imei], [d].[Model], [d].[Name], [d].[OsVersion], [d].[RowVersion], [g].[GpsBoxTypeID], [g].[GpsBoxSubTypeID], [g].[IconId], [g].[Name], [i].[IconId], [i].[Category], [i].[FileName], [i].[Icon], [g0].[GpsBoxTypeId], [g0].[Category], [g0].[IconId], [g0].[Name], [i0].[IconId], [i0].[Category], [i0].[FileName], [i0].[Icon], [v1].[VehiculeID], [v1].[BoardConfiguration], [v1].[BoardConnected], [v1].[BoardCurrentAddress], [v1].[BoardLastCommunicationTime], [v1].[Connected], [v1].[CurrentAddress], [v1].[CurrentDelay], [v1].[FuelConsumptionEstimationTime], [v1].[HeartBeatPeriod], [v1].[InsureCoherence], [v1].[KillHedgehog], [v1].[LastCommunicationTime], [v1].[LastConnexionTime], [v1].[LastParkMileage], [v1].[LastParkMileageTime], [v1].[NormalTrackingMode], [v1].[SmartModeDelay], [v1].[SmartModeDistance], [v1].[TimeModeDelay], [v1].[UpdateStartTime], [v1].[UpdateStatus], [v1].[VehiculeConfiguration], [g1].[ConfigurationID], [g1].[ConfigName], [g1].[Firmware], [g1].[GpsBoxType], [g1].[Master], [g1].[MasterName], [g1].[SimContract], [g1].[System], [a1].[AlertID], [a1].[AlertEnabled], [a1].[AlertRule], [a1].[Always], [a1].[CalendarID], [a1].[Category], [a1].[CompanyID], [a1].[Description], [a1].[DisplayName], [a1].[RowEnabled], [a1].[RowVersion], [a1].[Shared], [a1].[UserID]
FROM (
SELECT [a].[AlertDetailID], [a].[AckMachineName], [a].[AckPhoneNumber], [a].[AckTime], [a].[AckUserName], [a].[AlertDateTime], [a].[AlertID], [a].[AlertedCorridorId], [a].[AlertedItemId], [a].[AssociatedVehiculeID], [a].[AssociatedVehiculeUserID], [a].[Context], [a].[CustomID], [a].[CustomInfo], [a].[DbInsertTime], [a].[IsFleetAlert], [a].[MessageStatus], [a].[ReceivedTime], [a].[RowVersion], [a].[SafeProtectCustomInfo], [a].[TrackedVehiculeID], [a].[TrackedVehiculeUserID], [a0].[AlertID] AS [AlertID0]
FROM [AlertDetail] AS [a]
INNER JOIN [Alert] AS [a0] ON [a].[AlertID] = [a0].[AlertID]
LEFT JOIN [Vehicule] AS [v] ON [a].[TrackedVehiculeID] = [v].[VehiculeID]
WHERE (((((([a0].[CompanyID] = @__companyId_0) AND (CHARINDEX(N''SerializableContextAlert'', [a0].[AlertRule]) > 0)) AND [v].[VehiculeID] IS NOT NULL) AND ([v].[RowEnabled] = CAST(1 AS bit))) AND ([v].[CompanyID] = @__companyId_0)) AND (([v].[GpsBoxType] = 29) OR ([v].[GpsBoxType] = 12))) AND (CASE
WHEN [a].[AckTime] IS NOT NULL THEN CAST(1 AS bit)
ELSE CAST(0 AS bit)
END = @__acknwoledged_1)
ORDER BY [a].[AlertDateTime] DESC
OFFSET @__p_2 ROWS FETCH NEXT @__p_3 ROWS ONLY
) AS [t]
LEFT JOIN [Vehicule] AS [v0] ON [t].[TrackedVehiculeID] = [v0].[VehiculeID]
LEFT JOIN [SafeProtect].[Registration] AS [r] ON [v0].[VehiculeID] = [r].[VehiculeID]
LEFT JOIN [SafeProtect].[Device] AS [d] ON [v0].[VehiculeID] = [d].[VehiculeID]
LEFT JOIN [GpsBoxSubType] AS [g] ON ([v0].[GpsBoxType] = [g].[GpsBoxTypeID]) AND ([v0].[GpsBoxSubType] = [g].[GpsBoxSubTypeID])
LEFT JOIN [cst].[Icon] AS [i] ON [g].[IconId] = [i].[IconId]
LEFT JOIN [GpsBoxType] AS [g0] ON [v0].[GpsBoxType] = [g0].[GpsBoxTypeId]
LEFT JOIN [cst].[Icon] AS [i0] ON [g0].[IconId] = [i0].[IconId]
LEFT JOIN [VehiculeGpsBoxInfo] AS [v1] ON [v0].[VehiculeID] = [v1].[VehiculeID]
LEFT JOIN [GpsBoxConfiguration] AS [g1] ON [v1].[VehiculeConfiguration] = [g1].[ConfigurationID]
INNER JOIN [Alert] AS [a1] ON [t].[AlertID] = [a1].[AlertID]
ORDER BY [t].[AlertDateTime] DESC',N'@__companyId_0 int,@__acknwoledged_1 bit,@__p_2 int,@__p_3 int',@__companyId_0=1013,@__acknwoledged_1=0,@__p_2=0,@__p_3=999
TSQL 2:
exec sp_executesql N'SELECT [t].[AlertDetailID], [t].[AckMachineName], [t].[AckPhoneNumber], [t].[AckTime], [t].[AckUserName], [t].[AlertDateTime], [t].[AlertID], [t].[AlertedCorridorId], [t].[AlertedItemId],
[t].[AssociatedVehiculeID], [t].[AssociatedVehiculeUserID], [t].[Context], [t].[CustomID], [t].[CustomInfo], [t].[DbInsertTime], [t].[IsFleetAlert], [t].[MessageStatus], [t].[ReceivedTime], [t].[RowVersion],
[t].[SafeProtectCustomInfo], [t].[TrackedVehiculeID], [t].[TrackedVehiculeUserID], [v0].[VehiculeID], [v0].[Address], [v0].[AddressProtocol], [v0].[BoardID], [v0].[Category], [v0].[CompanyID], [v0].[CustomId], [v0].[DbInsertTime], [v0].[Description], [v0].[GpsBoxSubType], [v0].[GpsBoxTrackingDelay], [v0].[GpsBoxType], [v0].[HardwareID], [v0].[HasGeoWorker], [v0].[IconID], [v0].[Name], [v0].[PhoneNumber], [v0].[RowEnabled], [v0].[RowVersion], [v0].[VehiculeUserID], [r].[VehiculeID], [r].[CompanyId], [r].[LatestRegistrationStatusChangeDate], [r].[RegistrationMailSent], [r].[RegistrationStatusId], [d].[VehiculeID], [d].[AppVersion], [d].[Brand], [d].[Details], [d].[Imei], [d].[Model], [d].[Name], [d].[OsVersion], [d].[RowVersion], [g].[GpsBoxTypeID], [g].[GpsBoxSubTypeID], [g].[IconId], [g].[Name], [i].[IconId], [i].[Category], [i].[FileName], [i].[Icon], [g0].[GpsBoxTypeId], [g0].[Category], [g0].[IconId], [g0].[Name], [i0].[IconId], [i0].[Category], [i0].[FileName], [i0].[Icon], [v1].[VehiculeID], [v1].[BoardConfiguration], [v1].[BoardConnected], [v1].[BoardCurrentAddress], [v1].[BoardLastCommunicationTime], [v1].[Connected], [v1].[CurrentAddress], [v1].[CurrentDelay], [v1].[FuelConsumptionEstimationTime], [v1].[HeartBeatPeriod], [v1].[InsureCoherence], [v1].[KillHedgehog], [v1].[LastCommunicationTime], [v1].[LastConnexionTime], [v1].[LastParkMileage], [v1].[LastParkMileageTime], [v1].[NormalTrackingMode], [v1].[SmartModeDelay], [v1].[SmartModeDistance], [v1].[TimeModeDelay], [v1].[UpdateStartTime], [v1].[UpdateStatus], [v1].[VehiculeConfiguration], [g1].[ConfigurationID], [g1].[ConfigName], [g1].[Firmware], [g1].[GpsBoxType], [g1].[Master], [g1].[MasterName], [g1].[SimContract], [g1].[System], [a1].[AlertID], [a1].[AlertEnabled], [a1].[AlertRule], [a1].[Always], [a1].[CalendarID], [a1].[Category], [a1].[CompanyID], [a1].[Description], [a1].[DisplayName], [a1].[RowEnabled], [a1].[RowVersion], [a1].[Shared], [a1].[UserID]
FROM (
SELECT [a].[AlertDetailID], [a].[AckMachineName], [a].[AckPhoneNumber], [a].[AckTime], [a].[AckUserName], [a].[AlertDateTime], [a].[AlertID], [a].[AlertedCorridorId], [a].[AlertedItemId], [a].[AssociatedVehiculeID], [a].[AssociatedVehiculeUserID], [a].[Context], [a].[CustomID], [a].[CustomInfo], [a].[DbInsertTime], [a].[IsFleetAlert], [a].[MessageStatus], [a].[ReceivedTime], [a].[RowVersion], [a].[SafeProtectCustomInfo], [a].[TrackedVehiculeID], [a].[TrackedVehiculeUserID], [a0].[AlertID] AS [AlertID0]
FROM [AlertDetail] AS [a]
INNER JOIN [Alert] AS [a0] ON [a].[AlertID] = [a0].[AlertID]
LEFT JOIN [Vehicule] AS [v] ON [a].[TrackedVehiculeID] = [v].[VehiculeID]
WHERE ((((((([a0].[CompanyID] = @__companyId_0) AND (CHARINDEX(N''SerializableContextAlert'', [a0].[AlertRule]) > 0)) AND ([a].[AlertDateTime] >= @__startDate_1)) AND ([a].[AlertDateTime] <= @__endDate_2)) AND [v].[VehiculeID] IS NOT NULL) AND ([v].[CompanyID] = @__companyId_0)) AND ([v].[RowEnabled] = CAST(1 AS bit))) AND (([v].[GpsBoxType] = 29) OR ([v].[GpsBoxType] = 12))
ORDER BY (SELECT 1)
OFFSET @__p_3 ROWS FETCH NEXT @__p_4 ROWS ONLY
) AS [t]
LEFT JOIN [Vehicule] AS [v0] ON [t].[TrackedVehiculeID] = [v0].[VehiculeID]
LEFT JOIN [SafeProtect].[Registration] AS [r] ON [v0].[VehiculeID] = [r].[VehiculeID]
LEFT JOIN [SafeProtect].[Device] AS [d] ON [v0].[VehiculeID] = [d].[VehiculeID]
LEFT JOIN [GpsBoxSubType] AS [g] ON ([v0].[GpsBoxType] = [g].[GpsBoxTypeID]) AND ([v0].[GpsBoxSubType] = [g].[GpsBoxSubTypeID])
LEFT JOIN [cst].[Icon] AS [i] ON [g].[IconId] = [i].[IconId]
LEFT JOIN [GpsBoxType] AS [g0] ON [v0].[GpsBoxType] = [g0].[GpsBoxTypeId]
LEFT JOIN [cst].[Icon] AS [i0] ON [g0].[IconId] = [i0].[IconId]
LEFT JOIN [VehiculeGpsBoxInfo] AS [v1] ON [v0].[VehiculeID] = [v1].[VehiculeID]
LEFT JOIN [GpsBoxConfiguration] AS [g1] ON [v1].[VehiculeConfiguration] = [g1].[ConfigurationID]
INNER JOIN [Alert] AS [a1] ON [t].[AlertID] = [a1].[AlertID]
ORDER BY [t].[AlertDateTime] DESC',N'@__companyId_0 int,@__startDate_1 datetime,@__endDate_2 datetime,@__p_3 int,@__p_4 int',@__companyId_0=1013,@__startDate_1='2020-09-07 21:59:59',@__endDate_2='2020-09-08 21:59:59',@__p_3=0,@__p_4=999
我花了一些时间通过影响两个查询之间的差异来发现一个微小的差异。
如果你仔细看，第一个子查询包含一个 ORDER BY，这正是我想要的：
ORDER BY [a].[AlertDateTime] DESC
尽管使用相同的 OderBy，第二个 linq 查询被转换为包含
的 TSQL 子查询
ORDER BY (SELECT 1)
这听起来很疯狂。
我希望有人能解释一下这是怎么回事。
与过滤（Where）无关，与排序（OrderBy{Descending}）和行限制（Skip / Take）运算符的顺序无关LINQ 查询。
伪造的 ORDER BY (SELECT 1) 肯定是为具有以下片段的 LINQ 查询生成的
.Skip(0)
.Take(1000)
.OrderByDescending(ad => ad.AlertDateTime)
// .Skip(skip)
// .Take(take)
如您所见，此处行限制运算符在排序之前应用。由于 SqlServer OFFSET FETCH SQL 构造需要 ORDER BY，EF Core 转换器插入假的（最好抛出异常或让数据库这样做，但那是另一回事了。实际上在 EF 之前Core 3.0 有 CoreEventId.RowLimitingOperationWithoutOrderByWarning 可以配置为抛出，但由于某些未知原因，它已被废弃并且在 EF Core 3.x).
中无效
行限制的正确位置当然是 在 排序之后，因为它在注释掉的代码中。因此，只需删除（我猜是临时的）Skip(0).Take(1000) 并取消注释 .Skip(skip).Take(take)。问题已解决。
我有以下 Linq 查询，它们仅在 where 子句上有所不同：
查询 1：
var initialList = await
context.AlertDetailsDbSet
// Pouring the TrackedVehicule related graph
.Include(ad => ad.TrackedVehicule.Registration)
.Include(ad => ad.TrackedVehicule.Device)
.Include(ad => ad.TrackedVehicule.GpsBox.Icon)
.Include(ad => ad.TrackedVehicule.GpsBoxTypeNavigation.Icon)
.Include(ad => ad.TrackedVehicule.VehiculeGpsBoxInfo.VehiculeConfigurationNavigation)
// Loading the associated alert
.Include(ad => ad.Alert)
#if NETSTANDARD2_1
// This filter is not supported with EF Core 2.X
// It should be done client side
.Where(ad => ad.Alert.CompanyId == companyId && ad.Alert.AlertRule.Contains("SerializableContextAlert") && ad.AlertDateTime >= startDate && ad.AlertDateTime <= endDate && ad.TrackedVehicule != null && ad.TrackedVehicule.CompanyId == companyId && ad.TrackedVehicule.RowEnabled == true && (ad.TrackedVehicule.GpsBoxType == 29 || ad.TrackedVehicule.GpsBoxType == 12))
#endif
.Skip(0)
// A limit is applied on returned elements
.Take(1000)
.OrderByDescending(ad => ad.AlertDateTime)
// .Skip(skip)
// .Take(take)
// We disable the tracking mechanism because the context will be thrown away as soon as we have the data
.AsNoTracking()
// We want an asynchrounous execution
.ToListAsync(cancellationToken)
查询 2：
var initialList = await
context.AlertDetailsDbSet
// Pouring the TrackedVehicule related graph
.Include(ad => ad.TrackedVehicule.Registration)
.Include(ad => ad.TrackedVehicule.Device)
.Include(ad => ad.TrackedVehicule.GpsBox.Icon)
.Include(ad => ad.TrackedVehicule.GpsBoxTypeNavigation.Icon)
.Include(ad => ad.TrackedVehicule.VehiculeGpsBoxInfo.VehiculeConfigurationNavigation)
// Loading the associated alert
.Include(ad => ad.Alert)
#if NETSTANDARD2_1
// This filter is not supported with EF Core 2.X
// It should be done client side
.Where(ad => ad.Alert.CompanyId == companyId && ad.Alert.AlertRule.Contains("SerializableContextAlert") && ad.TrackedVehicule != null && ad.TrackedVehicule.RowEnabled == true && ad.TrackedVehicule.CompanyId == companyId && (ad.TrackedVehicule.GpsBoxType == 29 || ad.TrackedVehicule.GpsBoxType == 12) && ad.AckTime.HasValue == acknwoledged)
#endif
.OrderByDescending(ad => ad.AlertDateTime)
.Skip(skip)
.Take(take)
// We disable the tracking mechanism because the context will be thrown away as soon as we have the data
.AsNoTracking()
// We want an asynchrounous execution
.ToListAsync(cancellationToken)
基本上，第一个查询是（除其他事项外）过滤布尔值 属性，而第二个查询是 过滤范围日期.
我的问题是这些查询未转换为导致不同结果的相同 T-TSQL。
TSQL 1 :
exec sp_executesql N'SELECT [t].[AlertDetailID], [t].[AckMachineName], [t].[AckPhoneNumber], [t].[AckTime], [t].[AckUserName], [t].[AlertDateTime], [t].[AlertID], [t].[AlertedCorridorId], [t].[AlertedItemId],
[t].[AssociatedVehiculeID], [t].[AssociatedVehiculeUserID], [t].[Context], [t].[CustomID], [t].[CustomInfo], [t].[DbInsertTime], [t].[IsFleetAlert], [t].[MessageStatus], [t].[ReceivedTime], [t].[RowVersion],
[t].[SafeProtectCustomInfo], [t].[TrackedVehiculeID], [t].[TrackedVehiculeUserID], [v0].[VehiculeID], [v0].[Address], [v0].[AddressProtocol], [v0].[BoardID], [v0].[Category], [v0].[CompanyID], [v0].[CustomId], [v0].[DbInsertTime], [v0].[Description], [v0].[GpsBoxSubType], [v0].[GpsBoxTrackingDelay], [v0].[GpsBoxType], [v0].[HardwareID], [v0].[HasGeoWorker], [v0].[IconID], [v0].[Name], [v0].[PhoneNumber], [v0].[RowEnabled], [v0].[RowVersion], [v0].[VehiculeUserID], [r].[VehiculeID], [r].[CompanyId], [r].[LatestRegistrationStatusChangeDate], [r].[RegistrationMailSent], [r].[RegistrationStatusId], [d].[VehiculeID], [d].[AppVersion], [d].[Brand], [d].[Details], [d].[Imei], [d].[Model], [d].[Name], [d].[OsVersion], [d].[RowVersion], [g].[GpsBoxTypeID], [g].[GpsBoxSubTypeID], [g].[IconId], [g].[Name], [i].[IconId], [i].[Category], [i].[FileName], [i].[Icon], [g0].[GpsBoxTypeId], [g0].[Category], [g0].[IconId], [g0].[Name], [i0].[IconId], [i0].[Category], [i0].[FileName], [i0].[Icon], [v1].[VehiculeID], [v1].[BoardConfiguration], [v1].[BoardConnected], [v1].[BoardCurrentAddress], [v1].[BoardLastCommunicationTime], [v1].[Connected], [v1].[CurrentAddress], [v1].[CurrentDelay], [v1].[FuelConsumptionEstimationTime], [v1].[HeartBeatPeriod], [v1].[InsureCoherence], [v1].[KillHedgehog], [v1].[LastCommunicationTime], [v1].[LastConnexionTime], [v1].[LastParkMileage], [v1].[LastParkMileageTime], [v1].[NormalTrackingMode], [v1].[SmartModeDelay], [v1].[SmartModeDistance], [v1].[TimeModeDelay], [v1].[UpdateStartTime], [v1].[UpdateStatus], [v1].[VehiculeConfiguration], [g1].[ConfigurationID], [g1].[ConfigName], [g1].[Firmware], [g1].[GpsBoxType], [g1].[Master], [g1].[MasterName], [g1].[SimContract], [g1].[System], [a1].[AlertID], [a1].[AlertEnabled], [a1].[AlertRule], [a1].[Always], [a1].[CalendarID], [a1].[Category], [a1].[CompanyID], [a1].[Description], [a1].[DisplayName], [a1].[RowEnabled], [a1].[RowVersion], [a1].[Shared], [a1].[UserID]
FROM (
SELECT [a].[AlertDetailID], [a].[AckMachineName], [a].[AckPhoneNumber], [a].[AckTime], [a].[AckUserName], [a].[AlertDateTime], [a].[AlertID], [a].[AlertedCorridorId], [a].[AlertedItemId], [a].[AssociatedVehiculeID], [a].[AssociatedVehiculeUserID], [a].[Context], [a].[CustomID], [a].[CustomInfo], [a].[DbInsertTime], [a].[IsFleetAlert], [a].[MessageStatus], [a].[ReceivedTime], [a].[RowVersion], [a].[SafeProtectCustomInfo], [a].[TrackedVehiculeID], [a].[TrackedVehiculeUserID], [a0].[AlertID] AS [AlertID0]
FROM [AlertDetail] AS [a]
INNER JOIN [Alert] AS [a0] ON [a].[AlertID] = [a0].[AlertID]
LEFT JOIN [Vehicule] AS [v] ON [a].[TrackedVehiculeID] = [v].[VehiculeID]
WHERE (((((([a0].[CompanyID] = @__companyId_0) AND (CHARINDEX(N''SerializableContextAlert'', [a0].[AlertRule]) > 0)) AND [v].[VehiculeID] IS NOT NULL) AND ([v].[RowEnabled] = CAST(1 AS bit))) AND ([v].[CompanyID] = @__companyId_0)) AND (([v].[GpsBoxType] = 29) OR ([v].[GpsBoxType] = 12))) AND (CASE
WHEN [a].[AckTime] IS NOT NULL THEN CAST(1 AS bit)
ELSE CAST(0 AS bit)
END = @__acknwoledged_1)
ORDER BY [a].[AlertDateTime] DESC
OFFSET @__p_2 ROWS FETCH NEXT @__p_3 ROWS ONLY
) AS [t]
LEFT JOIN [Vehicule] AS [v0] ON [t].[TrackedVehiculeID] = [v0].[VehiculeID]
LEFT JOIN [SafeProtect].[Registration] AS [r] ON [v0].[VehiculeID] = [r].[VehiculeID]
LEFT JOIN [SafeProtect].[Device] AS [d] ON [v0].[VehiculeID] = [d].[VehiculeID]
LEFT JOIN [GpsBoxSubType] AS [g] ON ([v0].[GpsBoxType] = [g].[GpsBoxTypeID]) AND ([v0].[GpsBoxSubType] = [g].[GpsBoxSubTypeID])
LEFT JOIN [cst].[Icon] AS [i] ON [g].[IconId] = [i].[IconId]
LEFT JOIN [GpsBoxType] AS [g0] ON [v0].[GpsBoxType] = [g0].[GpsBoxTypeId]
LEFT JOIN [cst].[Icon] AS [i0] ON [g0].[IconId] = [i0].[IconId]
LEFT JOIN [VehiculeGpsBoxInfo] AS [v1] ON [v0].[VehiculeID] = [v1].[VehiculeID]
LEFT JOIN [GpsBoxConfiguration] AS [g1] ON [v1].[VehiculeConfiguration] = [g1].[ConfigurationID]
INNER JOIN [Alert] AS [a1] ON [t].[AlertID] = [a1].[AlertID]
ORDER BY [t].[AlertDateTime] DESC',N'@__companyId_0 int,@__acknwoledged_1 bit,@__p_2 int,@__p_3 int',@__companyId_0=1013,@__acknwoledged_1=0,@__p_2=0,@__p_3=999
TSQL 2:
exec sp_executesql N'SELECT [t].[AlertDetailID], [t].[AckMachineName], [t].[AckPhoneNumber], [t].[AckTime], [t].[AckUserName], [t].[AlertDateTime], [t].[AlertID], [t].[AlertedCorridorId], [t].[AlertedItemId],
[t].[AssociatedVehiculeID], [t].[AssociatedVehiculeUserID], [t].[Context], [t].[CustomID], [t].[CustomInfo], [t].[DbInsertTime], [t].[IsFleetAlert], [t].[MessageStatus], [t].[ReceivedTime], [t].[RowVersion],
[t].[SafeProtectCustomInfo], [t].[TrackedVehiculeID], [t].[TrackedVehiculeUserID], [v0].[VehiculeID], [v0].[Address], [v0].[AddressProtocol], [v0].[BoardID], [v0].[Category], [v0].[CompanyID], [v0].[CustomId], [v0].[DbInsertTime], [v0].[Description], [v0].[GpsBoxSubType], [v0].[GpsBoxTrackingDelay], [v0].[GpsBoxType], [v0].[HardwareID], [v0].[HasGeoWorker], [v0].[IconID], [v0].[Name], [v0].[PhoneNumber], [v0].[RowEnabled], [v0].[RowVersion], [v0].[VehiculeUserID], [r].[VehiculeID], [r].[CompanyId], [r].[LatestRegistrationStatusChangeDate], [r].[RegistrationMailSent], [r].[RegistrationStatusId], [d].[VehiculeID], [d].[AppVersion], [d].[Brand], [d].[Details], [d].[Imei], [d].[Model], [d].[Name], [d].[OsVersion], [d].[RowVersion], [g].[GpsBoxTypeID], [g].[GpsBoxSubTypeID], [g].[IconId], [g].[Name], [i].[IconId], [i].[Category], [i].[FileName], [i].[Icon], [g0].[GpsBoxTypeId], [g0].[Category], [g0].[IconId], [g0].[Name], [i0].[IconId], [i0].[Category], [i0].[FileName], [i0].[Icon], [v1].[VehiculeID], [v1].[BoardConfiguration], [v1].[BoardConnected], [v1].[BoardCurrentAddress], [v1].[BoardLastCommunicationTime], [v1].[Connected], [v1].[CurrentAddress], [v1].[CurrentDelay], [v1].[FuelConsumptionEstimationTime], [v1].[HeartBeatPeriod], [v1].[InsureCoherence], [v1].[KillHedgehog], [v1].[LastCommunicationTime], [v1].[LastConnexionTime], [v1].[LastParkMileage], [v1].[LastParkMileageTime], [v1].[NormalTrackingMode], [v1].[SmartModeDelay], [v1].[SmartModeDistance], [v1].[TimeModeDelay], [v1].[UpdateStartTime], [v1].[UpdateStatus], [v1].[VehiculeConfiguration], [g1].[ConfigurationID], [g1].[ConfigName], [g1].[Firmware], [g1].[GpsBoxType], [g1].[Master], [g1].[MasterName], [g1].[SimContract], [g1].[System], [a1].[AlertID], [a1].[AlertEnabled], [a1].[AlertRule], [a1].[Always], [a1].[CalendarID], [a1].[Category], [a1].[CompanyID], [a1].[Description], [a1].[DisplayName], [a1].[RowEnabled], [a1].[RowVersion], [a1].[Shared], [a1].[UserID]
FROM (
SELECT [a].[AlertDetailID], [a].[AckMachineName], [a].[AckPhoneNumber], [a].[AckTime], [a].[AckUserName], [a].[AlertDateTime], [a].[AlertID], [a].[AlertedCorridorId], [a].[AlertedItemId], [a].[AssociatedVehiculeID], [a].[AssociatedVehiculeUserID], [a].[Context], [a].[CustomID], [a].[CustomInfo], [a].[DbInsertTime], [a].[IsFleetAlert], [a].[MessageStatus], [a].[ReceivedTime], [a].[RowVersion], [a].[SafeProtectCustomInfo], [a].[TrackedVehiculeID], [a].[TrackedVehiculeUserID], [a0].[AlertID] AS [AlertID0]
FROM [AlertDetail] AS [a]
INNER JOIN [Alert] AS [a0] ON [a].[AlertID] = [a0].[AlertID]
LEFT JOIN [Vehicule] AS [v] ON [a].[TrackedVehiculeID] = [v].[VehiculeID]
WHERE ((((((([a0].[CompanyID] = @__companyId_0) AND (CHARINDEX(N''SerializableContextAlert'', [a0].[AlertRule]) > 0)) AND ([a].[AlertDateTime] >= @__startDate_1)) AND ([a].[AlertDateTime] <= @__endDate_2)) AND [v].[VehiculeID] IS NOT NULL) AND ([v].[CompanyID] = @__companyId_0)) AND ([v].[RowEnabled] = CAST(1 AS bit))) AND (([v].[GpsBoxType] = 29) OR ([v].[GpsBoxType] = 12))
ORDER BY (SELECT 1)
OFFSET @__p_3 ROWS FETCH NEXT @__p_4 ROWS ONLY
) AS [t]
LEFT JOIN [Vehicule] AS [v0] ON [t].[TrackedVehiculeID] = [v0].[VehiculeID]
LEFT JOIN [SafeProtect].[Registration] AS [r] ON [v0].[VehiculeID] = [r].[VehiculeID]
LEFT JOIN [SafeProtect].[Device] AS [d] ON [v0].[VehiculeID] = [d].[VehiculeID]
LEFT JOIN [GpsBoxSubType] AS [g] ON ([v0].[GpsBoxType] = [g].[GpsBoxTypeID]) AND ([v0].[GpsBoxSubType] = [g].[GpsBoxSubTypeID])
LEFT JOIN [cst].[Icon] AS [i] ON [g].[IconId] = [i].[IconId]
LEFT JOIN [GpsBoxType] AS [g0] ON [v0].[GpsBoxType] = [g0].[GpsBoxTypeId]
LEFT JOIN [cst].[Icon] AS [i0] ON [g0].[IconId] = [i0].[IconId]
LEFT JOIN [VehiculeGpsBoxInfo] AS [v1] ON [v0].[VehiculeID] = [v1].[VehiculeID]
LEFT JOIN [GpsBoxConfiguration] AS [g1] ON [v1].[VehiculeConfiguration] = [g1].[ConfigurationID]
INNER JOIN [Alert] AS [a1] ON [t].[AlertID] = [a1].[AlertID]
ORDER BY [t].[AlertDateTime] DESC',N'@__companyId_0 int,@__startDate_1 datetime,@__endDate_2 datetime,@__p_3 int,@__p_4 int',@__companyId_0=1013,@__startDate_1='2020-09-07 21:59:59',@__endDate_2='2020-09-08 21:59:59',@__p_3=0,@__p_4=999
我花了一些时间通过影响两个查询之间的差异来发现一个微小的差异。
如果你仔细看，第一个子查询包含一个 ORDER BY，这正是我想要的：
ORDER BY [a].[AlertDateTime] DESC
尽管使用相同的 OderBy，第二个 linq 查询被转换为包含
的 TSQL 子查询ORDER BY (SELECT 1)
这听起来很疯狂。
我希望有人能解释一下这是怎么回事。
与过滤（Where）无关，与排序（OrderBy{Descending}）和行限制（Skip / Take）运算符的顺序无关LINQ 查询。
伪造的 ORDER BY (SELECT 1) 肯定是为具有以下片段的 LINQ 查询生成的
.Skip(0)
.Take(1000)
.OrderByDescending(ad => ad.AlertDateTime)
// .Skip(skip)
// .Take(take)
如您所见，此处行限制运算符在排序之前应用。由于 SqlServer OFFSET FETCH SQL 构造需要 ORDER BY，EF Core 转换器插入假的（最好抛出异常或让数据库这样做，但那是另一回事了。实际上在 EF 之前Core 3.0 有 CoreEventId.RowLimitingOperationWithoutOrderByWarning 可以配置为抛出，但由于某些未知原因，它已被废弃并且在 EF Core 3.x).
行限制的正确位置当然是 在 排序之后，因为它在注释掉的代码中。因此，只需删除（我猜是临时的）Skip(0).Take(1000) 并取消注释 .Skip(skip).Take(take)。问题已解决。