How to use sync on a 3 model relationship? - Laravel - php

Question

I have 3 models:
Match Team Player
And i want to create a table with the following structure:
id | match_id | team_id | player_id
So that i can associate the 3 models i refered.
I created a 4th model MatchPlayers for the table i referred and I can use the 'search' functions without a problem. Like this:
$match->matchPlayers()->first()->team()->get()
And it returns the excpected result, but I cant do a
$match->matchPlayers()->sync([])
So, how should i solve this? Is my relationship wrong or the sync method isnt allowed on a 3 model relationship and I shoud use other method?
Thanks in advance
Edit:
Match.php
public function teamPlayers(){
return $this->hasMany('\Modules\Matchs\Entities\MatchPlayer');
}
Team.php
public function matchTeamPlayers(){
return $this->hasMany('\Modules\Matchs\Entities\MatchPlayer');
}
Player.php
public function matchTeamPlayers(){
return $this->hasMany('\Modules\Matchs\Entities\MatchPlayer');
}
MatchPlayer.php
public function player(){
return $this->belongsTo('\Modules\Players\Entities\Player');
}
public function match(){
return $this->belongsTo('\Modules\Matchs\Entities\Match');
}
public function team(){
return $this->belongsTo('\Modules\Teams\Entities\Team');
}

Answer 1

If you've followed the Laravel documentation on Pivot tables and Many-Many relationships found here, and it's still not working, you might have more luck with "Attach". For example;
$matchPlayer = MatchPlayer::create([...]);
$match->matchPlayers()->attach($matchPlayer)
A good example of sync vs attach can be found here

Answer 2

Using a fourth model for this kind of relationship makes sense, as it gives you a navigation property for the third relation on your pivot table. This way you can form more complex queries this way.
For your particular problem, syncing based on match_id and team_id, I would simply do something like this:
$matchId = 123;
$teamId = 234;
$rows = [
['match_id' => $matchId, 'team_id' => $teamId, 'player_id' => 345],
['match_id' => $matchId, 'team_id' => $teamId, 'player_id' => 346],
['match_id' => $matchId, 'team_id' => $teamId, 'player_id' => 347],
];
// remove all previously stored connections
MatchPlayer::where('match_id', $matchId)
->where('team_id', $teamId)
->delete();
// insert the news ones
// (you could also use MatchPlayer::create() per item or
// $matchPlayer->save(), it doesn't matter)
MatchPlayer::insert($rows);
If this operation occurs very frequently, you will potentially burn through a lot of id values of the pivot table. In this case you could also perform a more efficient sync, which is slightly more complex:
$matchId = 123;
$teamId = 234;
$rows = [
['match_id' => $matchId, 'team_id' => $teamId, 'player_id' => 345],
['match_id' => $matchId, 'team_id' => $teamId, 'player_id' => 346],
['match_id' => $matchId, 'team_id' => $teamId, 'player_id' => 347],
];
// delete all players that are not among the new data anymore
MatchPlayer::where('match_id', $matchId)
->where('team_id', $teamId)
->whereNotIn('player_id', array_pluck($rows, 'player_id'))
->delete();
// remove rows from new data that already exist
$exist = MatchPlayer::where('match_id', $matchId)
->where('team_id', $teamId)
->pluck('player_id')
->toArray();
$rows = array_filter($rows, function ($value, $key) use ($exist) {
return ! in_array($value['player_id'], $exist);
});
// then we store the remaining data
MatchPlayer::insert($rows);