问题描述

是否可以在两列上建立 hasMany 关系?

Is it possible to have a hasMany relationship on two columns?

我的表有两列，user_id 和 related_user_id.

My table has two columns, user_id and related_user_id.

我希望我的关系匹配任一列.

I want my relation to match either of the columns.

在我的模型中我有

public function userRelations()
{
    return $this->hasMany('AppUserRelation');
}

运行查询:select * from user_relations where user_relations.user_id in ('17', '18').

我需要运行的查询是:

select * from user_relations where user_relations.user_id = 17 OR user_relations.related_user_id = 17 

我正在使用预先加载，我认为这会影响它的工作方式.

I'm using eager loading and I think this will affect how it will have to work.

$cause = Cause::with('donations.user.userRelations')->where('active', '=', 1)->first();

推荐答案

我认为不可能完全按照您的要求去做.

I don't think it's possible to do exactly what you are asking.

我认为您应该将它们视为单独的关系，然后在模型上创建一个新方法来检索两者的集合.

I think you should treat them as separate relationships and then create a new method on the model to retrieve a collection of both.

public function userRelations() {
    return $this->hasMany('AppUserRelation');
}

public function relatedUserRelations() {
    return $this->hasMany('AppUserRelation', 'related_user_id');
}

public function allUserRelations() {
    return $this->userRelations->merge($this->relatedUserRelations);
}

通过这种方式，您仍然可以在模型上获得预先加载和关系缓存的好处.

This way you still get the benefit of eager loading and relationship caching on the model.

$cause = Cause::with('donations.user.userRelations', 
        'donations.user.relatedUserRelations')
    ->where('active', 1)->first();

$userRelations = $cause->donations[0]->user->allUserRelations();

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