Laravel Eloquent: how do I fix the N+1 query problem?

Question

My blog index page runs 101 queries for 100 posts because each post accesses `$post->author->name`. How do I reduce that?

Accepted Answer

Eager load the relationship with `with()`. That's 2 queries instead of 101:

```php
$posts = Post::with('author')->latest()->paginate(20);
```

Nested and constrained relations work too:

```php
Post::with(['author:id,name', 'comments' => fn ($q) => $q->latest()->limit(3)])->get();
```

To catch this automatically in development, add this to `AppServiceProvider::boot()`:

```php
Model::preventLazyLoading(! app()->isProduction());
```

Lazy loading then throws an exception, so N+1s get fixed before they reach production. Laravel Debugbar or Telescope show the query count per page.

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