Difference Between with() and load() in Laravel Eager Loading

When working with Eloquent relationships in Laravel, you'll often need to optimize your queries to avoid the N+1 problem. Laravel provides two primary methods for eager loading related models: with() and load(). While they serve similar purposes, they're used in different contexts. Let's explore the differences with practical examples.

What is Eager Loading?

Eager loading in Laravel is a powerful feature that allows you to load relationships along with your models to avoid the N+1 query problem. Laravel offers two main methods for eager loading relationships: with() and load().

you can read more in Laravel Official document: 

The with() Method

The with() method is used when you're building the initial query and know you'll need the related data. It eager loads relationships at the time of the parent query.

The with() method is used when writing your query, before the data is retrieved from the database.

Example of with()

// Eager load the 'comments' relationship at query time
$posts = Post::with('comments')->get();
foreach ($posts as $post) {
    // No additional query is executed here
    echo $post->comments->count();
}

In this example, Laravel will execute just two queries:

1. Get all posts
2. Get all comments for those posts

The load() Method

The load() method is used after you’ve already retrieved the model, to load its relationships.

Example of load()

public function show(Post $post)
{
    return $post->load('comments');
}

This also results in two queries, similar to the with() example, but the eager loading happens after the initial query.

Key Differences

1. Timing of Execution:
   • with(): Used during the initial query
   • load(): Used after models are already retrieved
2. Use Case:
   • Use with() when you know upfront you'll need the related data
   • Use load() when you need to conditionally load relationships
3. Method Chaining:
   • with() can be chained with other query builder methods
   • load() is called on an existing collection or model

Advanced Usage

Both methods support loading multiple relationships and nested relationships:

// Using with()
$posts = Post::with(['comments', 'author.profile'])->get();


// Using load()
$posts->load(['comments', 'author.profile']);

You can also fetch some specific column and Advanced Filtering with Closures to the eager loading:

Performance Considerations

Both methods result in the same number of queries when used properly. The choice between them depends on when you know you'll need the related data:

• If you always need the relationship, use with()
• If the relationship is needed conditionally, use load()

Conclusion

Understanding the difference between with() and load() helps you write more efficient Laravel applications. Remember:

• with() for eager loading during the initial query
• load() for eager loading after models are retrieved

Both methods help you avoid N+1 query problem, keeping your application fast and efficient.

Happy Coding! 😊