How can I implement single table inheritance using Laravel s Eloquent

Question

Currently I have a model class named Post.

class Post extends Eloquent {

    protected $table = 'posts';
    protected $fillable = array('user_id', 'title', 'description', 'views');

    /*
     * Relationships
     */

    public function user()
    {
        return $this->belongsTo('User');
    }

    public function tags()
    {
        return $this->belongsToMany('Tag', 'post_tags');
    }

    public function reactions()
    {
        return $this->hasMany('Reaction');
    }

    public function votes()
    {
        return $this->hasMany('PostVote');
    }

    //Scopes and functions...
}

What is the best way to do this and where to start?

Answer 1

Hello @kartik,

Global Scope is available:

class Article extends Post
{
    protected $table = 'posts';

    protected static function boot()
    {
        parent::boot();

        static::addGlobalScope('article', function (Builder $builder) {
            $builder->where('type', 'article');
        });

        static::creating(function ($article) {
            $article->type = 'article' 
        }); 
    }
}

where type = 'article' is added to all query of Article just like SoftDeletes.

>>> App\Article::where('id', 1)->toSql()
=> "select * from `posts` where `id` = ? and `type` = ?"

Actually laravel provide SoftDeletes trait using this feature.

Hope it helps!!