Reformat shown data - asp.net

Question

What's the easiest way to reformat data shown in the second view ?
I use .Net in the backend and Angular in the frontend.
I have a method that returns collection of attendances that has a collection of users with their statuses, and I can filter them to only query data in a date range.
I have no idea how to get the same data to get shown by users, since database structure is as follows:
Training has many schedules.
Schedules have Many Attendances.
Attendances have many Attendants and every Attendant has his status.
Now its easy to show data by attendances, but its impossible for me to figure out how to show data by attendants(users) to show all their attendances.
Is there any example someone could provide on something similar and how to do it in Asp, or angular.
I have tried creating new dto models, but I cant get neccessary data without using many queries, and mapping data too many times.
I have searched similar questions but didn't find anything relevant.
EDIT:
I am looking for the simplest solution.
I would like to know how to solve this both ways, and I can't decide which way is better ?
Here is the current method, which works for the first view:
public ICollection<AttendanceModel> ScheduleLog(int scheduleId, SearchAttendancesModel searchAttendances)
{
if (searchAttendances == null)
throw new ArgumentNullException("searchAttendances");
if (searchAttendances.Attendants == null)
throw new ArgumentNullException("searchAttendances.Attendants");
if (searchAttendances.AttendantStatuses == null)
throw new ArgumentNullException("searchAttendances.AttendantStatuses");
var query = _context
.Attendances
.Where(x=>x.ScheduleId==scheduleId)
.AsQueryable();
if (searchAttendances.FromDate != DateTime.MinValue)
{
query = query.
Where(x => x.Date >= searchAttendances.FromDate);
}
if (searchAttendances.ToDate != DateTime.MinValue)
{
query = query.
Where(x => x.Date <= searchAttendances.ToDate);
}
return query.ToList().Select(x => x.MapToAttendanceModel()).ToList();
}
It gets me the neccesary data to show for the first view, which I can easily show with tables thoru ng-repeat, but as I already said, I have many difficulties grouping data by user instead of by schedule, and then showing that data(all attendances per user) instead of all users per attendance.
Here is how my models look like:
This is schedule that has all the attendances:
public class ScheduleModel
{
public int Id { get; set; }
[Required]
public DateTime StartDate { get; set; }
[Required]
public DateTime EndDate { get; set; }
public string Description { get; set; }
public virtual ICollection<AttendanceModel> Attendances { get; set; }
}
This is attendance that has date for attendance and collection of attendants each of which have user and their status.
public class AttendanceModel
{
public int Id { get; set; }
[Required]
public DateTime Date { get; set; }
[Required]
public virtual ICollection<AttendantModel> Attendants { get; set; }
}
This is one Attendant that has user and status for that attendance
public class AttendantModel
{
public int Id { get; set; }
public virtual LookupModel ApplicantStatus { get; set; }
public virtual UserModel User { get; set; }
}