php Laravel 5 在两列上有许多关系
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Laravel 5 hasMany relationship on two columns
提问by CharliePrynn
Is it possible to have a hasMany relationship on two columns?
是否可以在两列上建立 hasMany 关系？
My table has two columns, user_idand related_user_id.
我的表有两列，user_id和related_user_id.
I want my relation to match either of the columns.
我希望我的关系匹配任一列。
In my model I have
在我的模型中，我有
public function userRelations()
{
return $this->hasMany('App\UserRelation');
}
Which runs the query: select * from user_relations where user_relations.user_id in ('17', '18').
它运行查询：select * from user_relations where user_relations.user_id in ('17', '18')。
The query I need to run is:
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
EDIT:
编辑：
I'm using eager loading and I think this will affect how it will have to work.
我正在使用预先加载，我认为这会影响它的工作方式。
$cause = Cause::with('donations.user.userRelations')->where('active', '=', 1)->first();
回答by Collin James
I don't think it's possible to do exactly what you are asking.
我认为不可能完全按照你的要求去做。
I think you should treat them as separate relationships and then create a new method on the model to retrieve a collection of both.
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。
public function userRelations() {
return $this->hasMany('App\UserRelation');
}
public function relatedUserRelations() {
return $this->hasMany('App\UserRelation', 'related_user_id');
}
public function allUserRelations() {
return $this->userRelations->merge($this->relatedUserRelations);
}
This way you still get the benefit of eager loading and relationship caching on the model.
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。
$cause = Cause::with('donations.user.userRelations',
'donations.user.relatedUserRelations')
->where('active', 1)->first();
$userRelations = $cause->donations[0]->user->allUserRelations();
回答by topclaudy
Composhipsadds support for multi-columns relationships in Laravel 5's Eloquent.
Compoships在 Laravel 5 的Eloquent 中添加了对多列关系的支持。
It allows you to specify relationships using the following syntax:
它允许您使用以下语法指定关系：
public function b()
{
return $this->hasMany('B', ['key1', 'key2'], ['key1', 'key2']);
}
where both columns have to match.
其中两列必须匹配。
回答by tomstig
If anyone landed here like me due to google: As neither merge() (as suggested above) nor push() (as suggested here) allow eager loading (and other nice relation features), the discussion is still ongoing and was continued in a more recent thread, see here: Laravel Eloquent Inner Join on Self Referencing Table
如果有人在这里登陆我一样，由于谷歌：由于没有合并（）（以上所建议的），也不推（）（如建议在这里）允许预先加载（和其他不错的关系特征），讨论仍在进行中，并继续在最近的线程，请参见此处：Laravel Eloquent Inner Join on Self Referencing Table
I proposed a solution there, any further ideas and contributions welcome.
我在那里提出了一个解决方案，欢迎任何进一步的想法和贡献。
回答by shamaseen
I'd prefer doing it this way:
我更喜欢这样做：
public function userRelations()
{
return UserRelation::where(function($q) {
/**
* @var Builder $q
*/
$q->where('user_id',$this->id)
->orWhere('related_user_id',$this->id);
});
}
public function getUserRelationsAttribute()
{
return $this->userRelations()->get();
}
