How to get parent_id name of category table from post table

Question

I have the following table in the "Category" table. id name parent_id1 student empty 2 teacher empty 3 math student 14 science student 1 I have the following table in the "Release" table. Post.php file in id name category_id1 Ajay 32 Mohan 3 model publicfunctioncategory(){return$this->belongsTo(Category::class,'category_id','id');} If I place the following code, I will get the third i

P粉393030917 · Answer

In the category model, add a parent relationship:

public function parent(){
        return $this->belongsTo(Category::class, 'parent_id', 'id')->withDefault();
    }

Then, you can get the parent name

$post->category->parent->name

P粉990008428 · Answer

You need to establish a relationship using parent_id to find the model instance for Category inside it.

In the Category.php model:

public function parent(){
    return $this->belongsTo(Category::class, 'parent_id', 'id');
}

Afterwards, you will be able to:

$post->category->parent->name;

id	Name	parent_id
1	student	null
2	teacher	null
3	MATHEMATICS STUDENT	1
4	Science Student	1

id	Name	category_id
1	阿杰	3
2	Mohan	3