如何在 3 模型关系上使用同步? - 拉拉维尔

Question

我有 3 个模型：

MatchTeamPlayer

我想创建一个具有以下结构的表：

id | match_id | team_id | player_id

这样我就可以将我引用的 3 个模型联系起来。

我为我提到的表创建了第 4 个模型MatchPlayers，我可以毫无问题地使用"搜索"功能。喜欢这个：

$match->matchPlayers()->first()->team()->get() 

它返回结果，但我无法执行

$match->matchPlayers()->sync([])

那么，我应该如何解决这个问题呢？我的关系是错误的还是 3 模型关系不允许同步方法，而我应该使用其他方法？

提前致谢

---

编辑：

Match.php
public function teamPlayers(){
return $this->hasMany('ModulesMatchsEntitiesMatchPlayer');
}
Team.php
public function matchTeamPlayers(){
return $this->hasMany('ModulesMatchsEntitiesMatchPlayer');
}
Player.php
public function matchTeamPlayers(){
return $this->hasMany('ModulesMatchsEntitiesMatchPlayer');
}
MatchPlayer.php
public function player(){
return $this->belongsTo('ModulesPlayersEntitiesPlayer');
}
public function match(){
return $this->belongsTo('ModulesMatchsEntitiesMatch');
}
public function team(){
return $this->belongsTo('ModulesTeamsEntitiesTeam');
}

Answer 1

如果您已经按照此处找到的数据透视表和多对多关系的Laravel文档进行操作，并且它仍然不起作用，那么"Attach"可能会更幸运。例如;

$matchPlayer = MatchPlayer::create([...]);
$match->matchPlayers()->attach($matchPlayer)

可以在此处找到同步与附加的一个很好的例子

Answer 2

对这种关系使用第四个模型是有意义的，因为它为您提供了数据透视表上第三个关系的导航属性。这样，您可以通过这种方式形成更复杂的查询。

对于您的特定问题，基于match_id和team_id进行同步，我只会做这样的事情：

$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);

---

如果此操作非常频繁地发生，则可能会烧毁数据透视表的大量id值。在这种情况下，您还可以执行更高效的同步，这稍微复杂一些：

$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);