Question

如何使用GroupBy查询TimeSpan，LINQPad查询LinqToSQL选择SQL Server平均值？

我已经尝试将所有内容转换为Ticks以及我能想到的所有其他内容但是我没有到达任何地方。

这是LINQ查询，您可能只需要注意结束，但我发布所有内容以防万一：

from so in TblServiceOrders 

where so.DateReceived!=null && 
      so.TimeReceived != null && 
      so.DateRequested!=null && 
      so.TimeRequested != null && 
      so.DateOpened != null && 
      so.TimeOpened != null


let DayReceived = so.DateReceived.Value.DayOfWeek
let DayRequested = so.DateRequested.Value.DayOfWeek
let DayOpened = so.DateOpened.Value.DayOfWeek

////Work out Business Hours in SLA
let SLADaysLapesed = ((so.DateRequested.Value.Day) - (so.DateReceived.Value.Day))

let SLAContainsWE = (DayReceived == DayOfWeek.Monday && SLADaysLapesed <= 4 ||
                     DayReceived == DayOfWeek.Tuesday && SLADaysLapesed <= 3 ||
                     DayReceived == DayOfWeek.Wednesday && SLADaysLapesed <= 2 ||
                     DayReceived == DayOfWeek.Thursday && SLADaysLapesed <= 1 ||
                     DayReceived == DayOfWeek.Friday && SLADaysLapesed <= 0 ? false : true )

let SLATotalDailyAH = (new TimeSpan(0, (930 * SLADaysLapesed), 0))

let TotalWEHours = (SLAContainsWE == true ? new TimeSpan(0,1020,0) : new TimeSpan(0,0,0))


let SLAHours =  (
                ((so.DateRequested.Value.AddHours(so.TimeRequested.Value.Hour)).AddMinutes(so.TimeRequested.Value.Minute)).Subtract
                ((so.DateReceived.Value.AddHours(so.TimeReceived.Value.Hour)).AddMinutes(so.TimeReceived.Value.Minute)).Subtract
                (SLATotalDailyAH).Subtract(TotalWEHours)
                )   


////Work out Business Hours in Passed before Job Opened
let OpenDaysLapesed = ((so.DateOpened.Value.Day) - (so.DateReceived.Value.Day))

let OpenContainsWE = (DayReceived == DayOfWeek.Monday && OpenDaysLapesed <= 4 ||
                     DayReceived == DayOfWeek.Tuesday && OpenDaysLapesed <= 3 ||
                     DayReceived == DayOfWeek.Wednesday && OpenDaysLapesed <= 2 ||
                     DayReceived == DayOfWeek.Thursday && OpenDaysLapesed <= 1 ||
                     DayReceived == DayOfWeek.Friday && OpenDaysLapesed <= 0 ? false : true )
let OpenTotalDailyAH = (new TimeSpan(0, (930 * OpenDaysLapesed), 0))

let TotalOpenWEHours = (OpenContainsWE == true ? new TimeSpan(0,1020,0) : new TimeSpan(0,0,0))


let OpenHours =  (
                 ((so.DateOpened.Value.AddHours(so.TimeOpened.Value.Hour)).AddMinutes(so.TimeOpened.Value.Minute)).Subtract
                 ((so.DateReceived.Value.AddHours(so.TimeReceived.Value.Hour)).AddMinutes(so.TimeReceived.Value.Minute)).Subtract
                 (OpenTotalDailyAH).Subtract(TotalOpenWEHours)
                 )  

group new {SLAHours, OpenHours} by "Total" into g



select new {
SLAHour = g.Average (x => x.SLAHours.Ticks),
OpenHour = g.Average (x => x.OpenHours.Ticks)
}

这是我在尝试执行查询时得到的StackTrace：

StackTrace    at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitMethodCall(SqlMethodCall mc)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitExpression(SqlExpression exp)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitMethodCall(SqlMethodCall mc)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitExpression(SqlExpression exp)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitMethodCall(SqlMethodCall mc)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitExpression(SqlExpression exp)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitMember(SqlMember m)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitExpression(SqlExpression exp)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitUnaryOperator(SqlUnary uo)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitUnaryOperator(SqlUnary uo)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitExpression(SqlExpression exp)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitRow(SqlRow row)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitSelectCore(SqlSelect select)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitSelect(SqlSelect select)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitAlias(SqlAlias a)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitSource(SqlSource source)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitSelectCore(SqlSelect select)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitSelect(SqlSelect select)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitAlias(SqlAlias a)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitSource(SqlSource source)
              at System.Data.Linq.SqlClient.SqlVisitor.VisitSelectCore(SqlSelect select)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Visitor.VisitSelect(SqlSelect select)
              at System.Data.Linq.SqlClient.SqlVisitor.Visit(SqlNode node)
              at System.Data.Linq.SqlClient.PostBindDotNetConverter.Convert(SqlNode node, SqlFactory sql, ProviderMode providerMode)
              at System.Data.Linq.SqlClient.SqlProvider.BuildQuery(ResultShape resultShape, Type resultType, SqlNode node, ReadOnlyCollection`1 parentParameters, SqlNodeAnnotations annotations)
              at System.Data.Linq.SqlClient.SqlProvider.BuildQuery(Expression query, SqlNodeAnnotations annotations)
              at System.Data.Linq.SqlClient.SqlProvider.System.Data.Linq.Provider.IProvider.Execute(Expression query)
              at System.Data.Linq.DataQuery`1.System.Collections.IEnumerable.GetEnumerator()
              at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
              at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source) 
HelpLink null 
Source System.Data.Linq 
HResult -2146233067

正如您可能知道的那样，我正在尝试使用LinqToSQL

完全在LINQPad4查询中运行此查询

如果我运行查询并选择全部“g”，则输出如下所示：

SLAHours      | OpenHours 
----------------------------
1.01:00:00    | 01:34:00 
27.02:32:00   | 125.06:06:00 
121.21:05:00  | 06:34:00 
29.17:36:00   | 1.04:44:00 
4.11:10:00    | 01:35:00 
4.19:26:00    | 1.03:26:00 
27.14:29:00   | 1.19:12:00 
04:01:00      | 00:14:00

== EDIT == 下面添加了一个更小的例子，似乎有一个类似的问题，我试图克服这个问题：

from so in TblServiceOrders 

where so.DateRequested!=null && 
      so.TimeRequested != null 

let SLAHours =  (so.DateRequested.Value.AddHours(so.TimeRequested.Value.Hour)).AddMinutes(so.TimeRequested.Value.Minute)

group new {open = SLAHours} by "Total" into g

select g.Average (x => x.open.Ticks)

短错误：成员'System.DateTime.Ticks'没有支持的SQL转换。

LINQPad如何GroupBy TimeSpan的平均值

0 个答案: