Question

我正在尝试按星期几获取行实例的总平均数。因此，在过去一年中，我试图获得星期一/星期二/星期二/星期日发生的平均骑行数量。

这是我到目前为止所拥有的。这给了我每周一天的总数，但不是平均数。

UnitOfWork.Query<WorkoutRecord>()
   .Where(x => x.WorkoutDate > baseDate)
   .GroupBy(x => SqlFunctions.DatePart("weekday", x.UploadDate))
   .Select(x => new AdminDashboardWorkoutsGroupedDay()
   {
       DayOfWeek = (DayOfWeek)x.Key,
       WorkoutCount = x.Count()
   }).ToList();

Answer 1

如果我理解你，最后你会尝试获得一个号码，即每个工作日的平均数。这需要第二次分组，将数据减少到一个组：

UnitOfWork.Query<WorkoutRecord>()
   .Where(x => x.WorkoutDate > baseDate)
   .GroupBy(x => SqlFunctions.DatePart("weekday", x.UploadDate))
   .Select(x => new AdminDashboardWorkoutsGroupedDay()
   {
       DayOfWeek = (DayOfWeek)x.Key,
       WorkoutCount = x.Count()
   })
   .GroupBy(g => 0) // or g => "x", or whatever
   .Select (g1 => (decimal)g1.Sum(x => x.WorkoutCount) / g1.Count())
   .ToList();

Answer 2

这是有效的。谢谢@Gert Arnold，你让我非常亲近。我不得不按天分组并计算所有训练时间，然后按工作日的平均值进行分组。

UnitOfWork.Query<WorkoutRecord>()
    .Where(x => x.WorkoutDate > baseDate && x.TotalTicks > 600)
    .GroupBy(x => EntityFunctions.TruncateTime(x.UploadDate))
    .Select(x => new 
    {
        Date = x.Key ?? DateTime.UtcNow,
        TheCount = x.Count()
    })
    .GroupBy(x=> SqlFunctions.DatePart("weekday", x.Date))
    .Select (x => new AdminDashboardWorkoutsGroupedDay()
    {
        WorkoutCount = (x.Average(y=>y.TheCount)),
        DayOfWeek = (DayOfWeek)x.Key
    })
    .ToList()

Answer 3

不清楚你想要的属性的平均值，但假设你有WorkoutRecord.Duration之类的属性，你应该能够得到平均值：

UnitOfWork.Query<WorkoutRecord>()
    .Where(x => x.WorkoutDate > baseDate)
    .GroupBy(x => SqlFunctions.DatePart("weekday", x.UploadDate))
    .Select(x => new AdminDashboardWorkoutsGroupedDay()
    {
        DayOfWeek = (DayOfWeek)x.Key,
        AverageDuration = x.Average(w => w.Duration)
    })
    .ToList();

Linq平均每周计算一次

3 个答案: