BCSH1-TournamentApp/TournamentOrganizer/Models/Participant.cs

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using Microsoft.EntityFrameworkCore;

namespace TournamentOrganizer.Models;

[PrimaryKey(nameof(RoundId), nameof(PlayerId))]
public class PlayerParticipant
{
    public int RoundId { get; set; }
    public int PlayerId { get; set; }

    public required Player Player { get; set; }
    public required Round Round { get; set; }
}

[PrimaryKey(nameof(MatchId), nameof(TeamId))]
public class TeamParticipant
{
    public int MatchId { get; set; }
    public int TeamId { get; set; }
    public int Seed { get; set; }
    public int Score { get; set; }

    public required Team Team { get; set; }
    public required Match Round { get; set; }
}