RoomRepository.cs

using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using EFLibSvcc.Models;
using Microsoft.EntityFrameworkCore;

namespace CarvedRock.Api.Repositories
{
    public class RoomRepository
    {
        private readonly svcodecampContext _dbContext;

        public RoomRepository(svcodecampContext dbContext)
        {
            _dbContext = dbContext;
        }

        public async Task<IEnumerable<LectureRooms>> GetAll()
        {
            return await _dbContext.LectureRooms.ToListAsync();
        }

        public async Task<IEnumerable<LectureRooms>> GetByCodeCampYear(string year)
        {
            var LectureRoomsIds = await (from session in _dbContext.Sessions
                join ccy in _dbContext.CodeCampYear on session.CodeCampYearId equals ccy.Id
                where ccy.UrlPostToken == year
                select session.LectureRoomsId).Distinct().ToListAsync();


            return await (from room in _dbContext.LectureRooms
                    orderby room.Number.ToLower()
                    where LectureRoomsIds.Contains(room.Id)
                    select room)
                .ToListAsync();
        }
    }
}