laravel - 合并模型及其与结果的关系，如 laravel 中的连接查询

Question

我是 Laravel 和编程的新手。我在加入模型及其关系时遇到问题，这是我的模型：

class MainClass extends Model
{
  public function first()
  {
    return $this->hasMany(First::class);
  }
  public function second()
  {
    return $this->hasMany(Second::class);
  }
  public function third()
  {
    return $this->hasMany(Third::class);
  }
}

当我尝试获取 MainClass 记录然后加载它的关系，如：

$main = Main::where('status', 'ready')->get()
$main->load(['first','second'])

这是我得到的：

[{
"id":"1",
"name":"First Person",
"status": "ready",
"first":[
         {"main_id": "1", "prop":"One"},
         {"main_id":"1", "prop":"Two"}],
"second":[
         {"main_id": "1", "other":"Yes"},
         {"main_id":"1", "other":"Two"},
         {"main_id":"1", "other":"Three"}]
},{
"id":"5",
"name":"Fifth Person",
"status": "ready",
"first":[
         {"main_id": "5", "prop":"Five"},
         {"main_id":"5", "prop":"Six"}],
"second":[
         {"main_id": "5", "other":"Laptop"},
        {"main_id":"5", "other":"Pc"}]
}]

我怎样才能合并这种关系，所以结果就像连接查询， 这就是我想要的：

[{
"id":"1",
"name":"First Person",
"status": "ready",
"prop":"One",
"other:"Yes"
},{
"id":"1",
"name":"First Person",
"status": "ready",
"prop":"Two",
"other":"Two"
}]

我知道有一种方法可以在 laravel 中将收集与合并或推送结合起来，但我似乎无法做到正确。

至于为什么不使用连接查询，因为我想动态加载关系，所以关系并不总是被加载，但有时它们会加载。在加入查询时，我必须手动编写（据我所知）:-)

也许有人可以指点我某个地方，或者也许有这样的包裹？

提前致谢

标签： laravellaravel-8eloquent-relationship

Answer 1

你可以通过加入来做到这一点；

$main = Main::query()->select(['main.id', 'main.name', 'main.status', 'f.prop', 's.other', 't.blabla'])
->leftJoin('first as f', 'f.main_id', 'main.id')
->leftJoin('second as s', 's.main_id', 'main.id')
->leftJoin('third as t', 't.main_id', 'main.id')
->where('main.status', 'ready')
->get();