实体框架中的分组和计数

Question

我有一张包含日志的表格，我每天计算的日志如下：

// Count logs by day
IList<DataModel> models = _context.Logs
  .Where(x => x.Created >= dateMinimum && x.Created <= dateMaximum)
  .GroupBy(x => new { Year = x.Created.Year, Month = x.Created.Month, Day = x.Created.Day })
  .Select(x => new { Year = x.Key.Year, Month = x.Key.Month, Day = x.Key.Day, Count = x.Count() })
  .AsEnumerable()
  .Select(x => new DataModel { Date = new DateTime(x.Year, x.Month, x.Day), LogsCount = x.Count })
  .ToList();

// Fill empty days with dates which contains all days in range
models.AddRange(dates.Where(x => !models.Any(y => y.Date == x.Date)).Select(x => new DataModel { Date = x, LogsCount = 0 }));

如果我想独立于类型按天计算所有日志，这是可行的。

但我想按天计算日志并输入类型（错误、警告、信息...）。

我尝试将 x.Type 添加到组，但最后我只得到 3 个项目。

目前我的数据模型如下：

public class DataModel
{
    public DateTime Date { get; set; }
    public Int32 LogsCount { get; set; }
}

但也许应该是这样的：

public class DataModel
{
    public DateTime Date { get; set; }
    public KeyValuePair<String, Int32> LogsCount { get; set; }
}

其中 LogsCount 有一个包含 Type 的字符串和包含计数的 Int32。

我该怎么做？

Answer 1

可能要考虑使用entity functions 按日期分组。

例子：

var results = query.GroupBy(r => new
{
    SentDate = System.Data.Objects.EntityFunctions.TruncateTime(r.Launch.EmailDeliveredDate),
    EventSubTypeID = r.EmailEventSubtypeID
})
.Select(x => new
{
    x.Key.SentDate,
    x.Key.EventSubTypeID,
    NumResults = x.Count()
})
.ToList();

Answer 2

你尝试过这样的事情吗？

IList<DataModel> models = Logs
  .Where(x => x.Created >= dateMinimum && x.Created <= dateMaximum)
  .GroupBy(x => new { Year = x.Created.Year, Month = x.Created.Month, Day = x.Created.Day, Type = x.Type })
  .Select(x => new { Year = x.Key.Year, Month = x.Key.Month, Day = x.Key.Day, Count = x.Count(), Type = x.Key.Type })
  .AsEnumerable()
  .Select(x => new DataModel { Date = new DateTime(x.Year, x.Month, x.Day), LogsCount = x.Count, Type = x.Type })
  .ToList()


public class DataModel
{
    public DateTime Date { get; set; }
    public Int32 LogsCount { get; set; }
    public string Type { get; set; }
}