How can you implement single table inheritance for Article and Question models using Laravel\'s Eloquent, extending from the Post model?

Implementing Single Table Inheritance Using Laravel's Eloquent

Question:

Given the Post model:

<code class="php">class Post extends Eloquent {

    // Model code...
}</code>

How can you implement inheritance for Article and Question models, allowing them to extend from Post?

Single Table Inheritance

Single table inheritance involves storing all model data in a single table with a type column to differentiate models. However, this approach can lead to numerous NULL values due to unused columns for specific model types.

Multi Table Inheritance

Multi table inheritance employs polymorphism, utilizing separate tables for each model while connecting them through a reference table. The reference table includes columns like postable_id and postable_type.

Eloquent Model Setup

In the Post model, define a morphTo relationship:

<code class="php">public function postable(){
    return $this->morphTo();
}</code>

In the Question model (similar for Article):

<code class="php">public function post(){
    return $this->morphOne('Post', 'postable');
}</code>

Usage:

• Retrieve all posts: Post::all()
• Retrieve all questions: Question::all()
• Get question details from a post: $question_column2 = $post->postable->question_column2
• Check post type: if($post->postable instanceof Question)
• Create a new question:

<code class="php">$post = new Post();
$post->shared_column = 'New Question Post';
$post->save();

$question = new Question();
$question->question_column = 'test';
$question->post()->save($post);</code>

Conclusion

Multi table inheritance offers a more efficient database structure compared to single table inheritance. It requires additional model logic, but it provides a more flexible and scalable approach for handling model inheritance in Laravel's Eloquent.

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