docker.tar.gz

Serve /usercode

Run index.php (quiet composer install)

Serve /usercode (quiet composer install)

execute_apcu

This course is for people who have already learned the basics of PHP (or just finished the "Learn PHP from Scratch" course) and want the bigger picture of making big web applications with this language.

First, you'll learn how all PHP web applications communicate with the world and how to turn multiple source code files into one application. Then you'll learn multiple approaches to structuring the whole application. It will help you write code that's easy to maintain. Also, this is a common topic for job interview questions.

Next, you'll learn different data storage methods, from user sessions to databases. This course doesn't duplicate the official documentation but instead provides an overview of the various tools you can use. You'll learn how to use them in PHP, their tradeoffs, and how to pick what's best for your project.

Finally, you'll learn how to make automated tests for your project to ensure that it works as expected.

Developing Web Applications with PHP

Relational databases provide us with a tool for improved consistency. We can feel secure knowing that our application can crash during a complex update because of **database transactions**.

Some updates require multiple database queries, and an error in the middle of an update can leave the database in an invalid state. Database transactions solve this issue by grouping multiple SQL commands into one big update.

## Why do we need transactions?


Let’s look again at our example schema for a theater application. This time we’re interested in the `orders` and `tickets` tables. And, this time, the `orders` table has an `amount` property containing the amount of money we want to request from the user.

Relational databases provide us with a tool for improved consistency. We can feel secure knowing that our application can crash during a complex update because of **database transactions**.

Some updates require multiple database queries, and an error in the middle of an update can leave the database in an invalid state. Database transactions solve this issue by grouping multiple SQL commands into one big update.

# Why do we need transactions?


Let’s look again at our example schema for a theater application. This time we’re interested in the `orders` and `tickets` tables. And, this time, the `orders` table has an `amount` property containing the amount of money we want to request from the user.

Learn how to ensure data consistency using database transactions, what ACID means, and what we can do when transactions are unavailable.

Introduction

Communicating with the Client

Static Web Application

Structuring Code Files

Application Architecture Basics

PHP-Based Web Application

Storing State

Databases

Using a Database in the PHP Application

Testing

Testing the PHP Application

Advanced Architecture Patterns

Final Assessment

Conclusion

Database Transactions

Why do we need transactions?