Laravel Eager Loading: Fetch Specific Columns in Relationships Using with()

Eager loading in Laravel (using with()) prevents the N+1 query problem, but did you know you can optimize it further by selecting only the columns you need? This improves memory usage and query speed.

3 Ways to Select Specific Columns Using with() function

Method 1: Simple Column Selection

$posts = Post::query()->latest()->with('author:id,name');

• Most concise syntax
• Works for simple cases where you just need specific columns
• Requires the foreign key (typically id) to be included for the relationship to work

Method 2: Closure-Based Column Selection

$posts = Post::query()->latest()->with([
    'author' => function ($query) {
        $query->select('id', 'name');
    }
]);

• More flexible approach
• Allows additional query constraints
• Can add other clauses like where, orderBy, etc.

Method 3: Defined in Model Relationship

// In your Post model
public function author()
{
    return $this->belongsTo(User::class, 'author_id')->select('id', 'name');
}

• Most maintainable for frequently used column selections
• Applies consistently wherever the relationship is used
• Can be overridden in queries when needed

Important Notes:

1. Always include the primary key (and foreign key if different) in your selected columns
2. Method 3 affects all queries using this relationship, which may not always be desirable
3. For complex relationship queries, Method 2 provides the most flexibility

Choose the method that best fits your specific use case and application architecture.

Happy Coding! 😊