How to use recursive relation in laravel?

@elisha_langworth 

In Laravel, a recursive relation allows you to define a relationship between a model and itself. This is commonly used in scenarios where a model can have a parent-child relationship within the same table.

To use a recursive relation in Laravel, you first need to define the relationship in your model. Let's say you have a model called Category and each category can have a parent category:

1. Define the relationship in your Model:

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namespace App;

use IlluminateDatabaseEloquentModel;

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

    public function children()
    {
        return $this->hasMany(Category::class, 'parent_id');
    }
}

In this example, the Category model has two relation methods: parent() and children(). The parent() method defines the belongsTo relationship with itself, indicating that a category can belong to a parent category. The children() method defines the hasMany relationship with itself, indicating that a category can have multiple child categories.

1. Use the recursive relation in your application code:

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$category = Category::find(1);

// Get the parent category
$parentCategory = $category->parent;

// Get the child categories
$childCategories = $category->children;

In this code snippet, we retrieve a specific category by its ID and then use the parent() and children() methods to access its parent category and child categories, respectively.

By defining and using recursive relations in Laravel, you can easily work with hierarchical data structures and build complex relationships within your application.