Database Optimization Techniques for Laravel Applications.

Optimizing database performance is an essential aspect of building robust web applications.

There are several ways to optimize a database, some of which include Indexing, Proper schema design, Data normalization, Query optimization, Partitioning, Compression, and Proper hardware selection. In this blog post, I will focus on database caching.

In this article, we'll explore how to optimize the performance of your database-driven Laravel application using caching. Caching is a powerful technique that can significantly reduce the number of queries needed to retrieve data, resulting in faster response times and improved user experience.

Laravel offers several caching mechanisms, including file caching, database caching, and Redis caching. Each mechanism has its own strengths and weaknesses, and the choice of which to use will depend on your application's specific needs and requirements.

To implement caching in your Laravel application, you can use the built-in caching functions and cache drivers provided by Laravel. You can also use third-party packages and libraries for more advanced caching functionality.

However, caching also has its potential drawbacks, such as increased memory usage and the need for cache invalidation. To mitigate these issues, it is important to use a consistent naming convention for cache keys and to group related data using cache tags.

To measure the effectiveness of caching in your application, you can use benchmarking and profiling tools to analyze your application's performance before and after implementing caching.

By following these best practices for implementing caching in your Laravel application, you can improve its overall performance and provide a better user experience for your users.

By default, Laravel is configured to use the file cache driver, which stores the serialized, cached objects on the server's filesystem. For larger applications, it is recommended that you use a more robust driver such as Memcached or Redis. You may even configure multiple cache configurations for the same driver. I'm going to be using the default cache driver in this article.

In this example, we have a restaurant application that allows users to place orders and make table reservations. The application heavily relies on database transactions, which can result in slow performance and reduced user experience if not optimized. One effective way to optimize the performance of the application is by implementing database caching.

Caching can help reduce the number of database queries needed to retrieve data and improve application responsiveness. In our restaurant application, we can cache the cart items that users add to their orders and reservations. By caching the cart items, we can reduce the number of queries needed to retrieve the items from the database and improve application performance.

To implement caching in our restaurant application, we can leverage Laravel's caching mechanism. We can use Laravel's built-in caching functions and cache drivers to store the cart items in a cache store. We can also use Laravel's observer to delete cached data when the state of the cart items changes. For example, when a user adds new items to their cart or performs CRUD operations on the cart model, the observer can automatically invalidate the cache store and ensure that the latest data is retrieved from the database.

Additionally, we can use cache tags to group related data and improve cache invalidation. By assigning tags to our cached data, we can easily invalidate related data when necessary and avoid clearing the entire cache store.

To measure the effectiveness of our caching strategy in the restaurant application, we can use benchmarking and profiling tools like Clockwork. Clockwork is a free and open-source tool that can help us analyze the performance of our application before and after implementing caching.

We can use Clockwork to track the number of database queries executed, the time taken to execute each query, and the memory used by the application. This information can help us identify any performance bottlenecks and optimize our caching strategy for maximum performance.
To get started, we need to install Clockwork in our Laravel project via Composer. You can do this by running the following command in your terminal:

composer require --dev itsgoingd/clockwork

Now download the browser extension of Clockwork. Let's dive in!

class CartController extends Controller
{
    //
    public function index(){
        return view('frontend.cart', [
            'carts' => Cache::remember('cart', 60, function () {
                return Cart::where('user_id', auth()->user()->id())->get();
            })
        ]);
    }
}

Let me explain the code above, this code block is a method in a Laravel controller that is used to display a user's shopping cart on the frontend of a web application. The index() method retrieves the cart items from the database using the Cart model and then stores the retrieved data in the cache for 60 seconds using the Cache::remember() method.

The Cache::remember() method takes three parameters: the key for the cached data, the time-to-live (TTL) in minutes, and a closure that retrieves the data to be cached. In this case, the key is 'cart', the TTL is 60 minutes, and the closure returns the cart items from the database using the Cart::where() query builder method.

Once the cart items have been retrieved and cached, they are passed to the frontend.cart view using the view() helper function. The cached cart items are then accessed in the view using the $carts variable, which contains the cached data.

Now let's create an observer for the cart model by using php artisan make:observer CartObserver --model=Cart.

Laravel will then generate a new PHP file with method resource and we'll use this observer to clear our cached data whenever our Cart model changes state.

<?php

namespace App\Observers;

use App\Models\Cart;
use Illuminate\Support\Facades\Cache;

class CartObserver
{
    /**
     * Handle the Cart "created" event.
     *
     * @param  \App\Models\Cart  $cart
     * @return void
     */
    public function created(Cart $cart)
    {
        //
        Cache::forget('cart');
    }

    /**
     * Handle the Cart "updated" event.
     *
     * @param  \App\Models\Cart  $cart
     * @return void
     */
    public function updated(Cart $cart)
    {
        //
        Cache::forget('cart');
    }

    /**
     * Handle the Cart "deleted" event.
     *
     * @param  \App\Models\Cart  $cart
     * @return void
     */
    public function deleted(Cart $cart)
    {
        //
        Cache::forget('cart');
    }

    /**
     * Handle the Cart "restored" event.
     *
     * @param  \App\Models\Cart  $cart
     * @return void
     */
    public function restored(Cart $cart)
    {
        //
    }

    /**
     * Handle the Cart "force deleted" event.
     *
     * @param  \App\Models\Cart  $cart
     * @return void
     */
    public function forceDeleted(Cart $cart)
    {
        //
        Cache::forget('cart');
    }
}

Now, let's use Clockwork to compare the performance before and after implementing caching. This will help us determine the impact of caching on our application's performance.

Before caching:

After caching:

Before implementing caching, our application made nine database queries in seventeen milliseconds. After implementing caching, we observed a significant improvement in performance, as our application made only eight queries in just eight milliseconds. The difference here is not only in the time recorded but also in the number of queries made.

By caching frequently accessed data like cart items, we were able to reduce the number of queries needed to retrieve data from the database. This resulted in faster response times and improved overall performance. Imagine the impact of implementing caching on other frequently accessed data in our application - it can be mind-blowing!

Caching is a powerful technique that can significantly improve the performance of database-driven applications. By reducing the number of database queries needed to retrieve data, caching can improve application responsiveness and user experience. It is important to choose the right caching strategy based on your application's specific needs and requirements to achieve the best results.

Thanks for reading! I hope this article has been helpful in understanding the benefits of database caching and how to implement it in Laravel. If you have any questions or feedback, feel free to reach out to me on twitter or Github. Don't forget to follow me for more articles and updates.