How to handle PHP PDO transactions with deadlocks in MySQL 8.0?
I'm building a feature where I'm migrating some code and I need some guidance on I've been researching this but I'm migrating some code and After trying multiple solutions online, I still can't figure this out... I'm currently experiencing issues with deadlocks when using PHP's PDO to perform transactions with MySQL 8.0. I have a simple script that handles user registrations and updates user records, but occasionally, I encounter the `Deadlock found when trying to get lock; try restarting transaction` behavior. Here’s a simplified version of my code: ```php try { $pdo = new PDO('mysql:host=localhost;dbname=mydb', 'username', 'password'); $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $pdo->beginTransaction(); // Insert new user $stmt = $pdo->prepare('INSERT INTO users (username, email) VALUES (:username, :email)'); $stmt->execute([':username' => $username, ':email' => $email]); // Update another record $stmt = $pdo->prepare('UPDATE accounts SET last_active = NOW() WHERE user_id = :user_id'); $stmt->execute([':user_id' => $userId]); $pdo->commit(); } catch (PDOException $e) { if ($e->getCode() == '40001') { // Deadlock behavior code $pdo->rollBack(); echo 'Deadlock detected, transaction rolled back.'; } else { echo 'Database behavior: ' . $e->getMessage(); } } ``` I’ve tried adding retries for the transaction but it doesn’t seem to completely solve the scenario. I've also read that the order of operations can affect deadlock occurrences, yet my operations are fairly straightforward. What best practices should I implement to reduce or completely avoid these deadlocks in my PDO transactions? Are there specific patterns or configurations in MySQL 8.0 that I should be aware of? What am I doing wrong? Has anyone dealt with something similar? This is happening in both development and production on Debian. Am I approaching this the right way? I've been using Php for about a year now. I recently upgraded to Php 3.11. Is there a better approach? This is happening in both development and production on Linux. This is part of a larger microservice I'm building. Hoping someone can shed some light on this.