Laravel Eloquent with()-> 返回 null
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Laravel Eloquent with()-> returning null
提问by Jazzy
I am trying to use Eloquent to get a specific product that has a brand_idcolumn that maps to a brandstable, the brandarray is coming back empty.
我正在尝试使用 Eloquent 来获取具有brand_id映射到brands表的列的特定产品，该brand数组返回空。
Is there anything obvious here that needs to be changed?
这里有什么明显的需要改变的吗？
$product = Product::with('images')->with('brand')->select($fields)->where('display', '=', 1)->find($id);
//Product model
//产品型号
class Product extends Eloquent {
...
public function brand()
{
return $this->belongsTo('Brand');
}
//Brand model
//品牌型号
class Brand extends Eloquent {
...
public function products()
{
return $this->hasMany('Product');
}
回答by The Alpha
You have this:
你有这个：
$product = Product::with('images', 'brand')
->select($fields)
->where('display', 1)
->find($id);
You are getting nullfor brandand it could be because you have some specific fields and most probably you didn't select the foreing_keyfrom the productstable that creates the relationship with Brand, so if your productstable contains the foreign_key(probably brand_id) of brandtable then you have to select that foreign_keyfrom the productstable too. So, just add that foreign_key/brand_idin the $fieldsvariable. Without the relation builder key (FK) the Brandwon't be loaded.
你得到null的brand，它可能是因为你有一些特定的领域和最可能是你没有选择foreing_key从products创建与关系表Brand，因此，如果您的products表包含的foreign_key（可能brand_id）的brand表，那么你必须选择foreign_key从该products表也。所以，只要添加foreign_key/brand_id的$fields变量。没有关系构建器键 ( FK)Brand将不会被加载。
