Laravel Eloquent 多个 wheres 给出了错误的结果答案

【问题标题】：Laravel Eloquent multiple wheres gives wrong resultsLaravel Eloquent 多个 wheres 给出了错误的结果
【发布时间】：2022-01-17 03:42:42
【问题描述】：

为什么下面的代码返回错误的结果？

        $player->wins = Game::where('home_player_1', '=', $player->id)
                            ->orWhere('home_player_2', '=', $player->id)
                            ->orWhere('home_player_3', '=', $player->id)
                            ->orWhere('home_player_4', '=', $player->id)
                            ->where('result', '=','1') // 1 = win
                            ->get();

        $player->losses = Game::where('home_player_1', '=', $player->id)
                            ->orWhere('home_player_2', '=', $player->id)
                            ->orWhere('home_player_3', '=', $player->id)
                            ->orWhere('home_player_4', '=', $player->id)
                            ->where('result', '=','0') // 0 = lose
                            ->get();

        $player->matches = Game::where('home_player_1', '=', $player->id)
                            ->orWhere('home_player_2', '=', $player->id)
                            ->orWhere('home_player_3', '=', $player->id)
                            ->orWhere('home_player_4', '=', $player->id)
                            ->get();

我得到的结果就像是 5 场比赛 / 5 场胜利 / 5 场失败，而实际上是 5/5/0。我该怎么做？

【问题讨论】：

标签： laravel eloquent

【解决方案1】：

将您的 home_player_x 子句移动到嵌套 where 条件子句中：

$player->wins = Game::where(function ($query) use ($player) {
  return $query->where('home_player_1', $player->id)
  ->orWhere('home_player_2', $player->id)
  ->orWhere('home_player_3', $player->id)
  ->orWhere('home_player_4', $player->id);
})->where('result', 1)
->get();

...

这样，它不会与最后一个 ->where('result') 子句冲突。

此外，由于您多次重用此子句，请将其定义为变量并重用：

$conditional = function ($query) use ($player) {
  return $query->where(function ($subQuery) use ($player) {
    return $subQuery->orWhere('home_player_1', $player->id)
    ->orWhere('home_player_2', $player->id)
    ->orWhere('home_player_3', $player->id)
    ->orWhere('home_player_4', $player->id);
  })
});

$player->wins = Game::where($conditional)->where('result', 1)->get();
$player->losses = Game::where($conditional)->where('result', 0)->get();
$player->matches = Game::where($conditional)->get();

或者，考虑将其定义为 Game 模型上的 Scope，以便您可以调用 Game::playerMatches($player)->where('result', 1)->get() 等。请参阅文档：

https://laravel.com/docs/8.x/eloquent#local-scopes

我不会对此进行过多介绍，但定义编号列，如home_player_1、home_player_2 等通常被认为是不好的数据做法。您应该定义一个home_players 表或games_players，其中type 列用于home 或away 表，并以这种方式关联Game 和Players。

【讨论】：

谢谢，正如你所说，无论如何我都会改变我的数据库结构。

【解决方案2】：

查看 Laravel 文档中Logical Grouping 上的帖子。我认为基于此，您对matches 的声明应该是：

$player->matches = Game::where(function ($query) use ($player) {
    $query->where('home_player_1', '=', $player->id)
          ->orWhere('home_player_2', '=', $player->id)
          ->orWhere('home_player_3', '=', $player->id)
          ->orWhere('home_player_4', '=', $player->id);
})->get();

我不确定这是否有帮助，因为我没有其余的代码，但请测试它并告诉我。

也来自文档： "In fact, you should generally always group calls to the orWhere method in parentheses in order to avoid unexpected query behavior."

【讨论】：

谢谢@TimLewis 我更新了我的答案。

【解决方案3】：

需要修改orWhere()条件，可以用下面的where子句代替上面的：

$player->wins = Game::where('result', '=','1') // 1 = win
    ->where(function ($query) use ($player) {
        $query->where('home_player_1', '=', $player->id)
            ->orWhere('home_player_2', '=', $player->id)
            ->orWhere('home_player_3', '=', $player->id)
            ->orWhere('home_player_4', '=', $player->id);
    })->get();

$player->losses = Game::where('result', '=', '0') // 0 = lose
    ->where(function ($query) use ($player) {
        $query->where('home_player_1', '=', $player->id)
            ->orWhere('home_player_2', '=', $player->id)
            ->orWhere('home_player_3', '=', $player->id)
            ->orWhere('home_player_4', '=', $player->id);
    })->get();


$player->matches = Game::
    where(function ($query) use ($player) {
        $query->where('home_player_1', '=', $player->id)
            ->orWhere('home_player_2', '=', $player->id)
            ->orWhere('home_player_3', '=', $player->id)
            ->orWhere('home_player_4', '=', $player->id);
    })->get();

当有多个 orWhere() 时，正常情况不起作用，需要在单个 where 下添加它们。

【讨论】：