Common interview questions for PHP outsourcing companies

PHPisstillrelevantinmodernenterpriseenvironments.1.ModernPHP(7.xand8.x)offersperformancegains,stricttyping,JITcompilation,andmodernsyntax,makingitsuitableforlarge-scaleapplications.2.PHPintegrateseffectivelyinhybridarchitectures,servingasanAPIgateway

Avoid N 1 query problems, reduce the number of database queries by loading associated data in advance; 2. Select only the required fields to avoid loading complete entities to save memory and bandwidth; 3. Use cache strategies reasonably, such as Doctrine's secondary cache or Redis cache high-frequency query results; 4. Optimize the entity life cycle and call clear() regularly to free up memory to prevent memory overflow; 5. Ensure that the database index exists and analyze the generated SQL statements to avoid inefficient queries; 6. Disable automatic change tracking in scenarios where changes are not required, and use arrays or lightweight modes to improve performance. Correct use of ORM requires combining SQL monitoring, caching, batch processing and appropriate optimization to ensure application performance while maintaining development efficiency.

To build a flexible PHP microservice, you need to use RabbitMQ to achieve asynchronous communication, 1. Decouple the service through message queues to avoid cascade failures; 2. Configure persistent queues, persistent messages, release confirmation and manual ACK to ensure reliability; 3. Use exponential backoff retry, TTL and dead letter queue security processing failures; 4. Use tools such as supervisord to protect consumer processes and enable heartbeat mechanisms to ensure service health; and ultimately realize the ability of the system to continuously operate in failures.

The settings.json file is located in the user-level or workspace-level path and is used to customize VSCode settings. 1. User-level path: Windows is C:\Users\\AppData\Roaming\Code\User\settings.json, macOS is /Users//Library/ApplicationSupport/Code/User/settings.json, Linux is /home//.config/Code/User/settings.json; 2. Workspace-level path: .vscode/settings in the project root directory

Using the correct PHP basic image and configuring a secure, performance-optimized Docker environment is the key to achieving production ready. 1. Select php:8.3-fpm-alpine as the basic image to reduce the attack surface and improve performance; 2. Disable dangerous functions through custom php.ini, turn off error display, and enable Opcache and JIT to enhance security and performance; 3. Use Nginx as the reverse proxy to restrict access to sensitive files and correctly forward PHP requests to PHP-FPM; 4. Use multi-stage optimization images to remove development dependencies, and set up non-root users to run containers; 5. Optional Supervisord to manage multiple processes such as cron; 6. Verify that no sensitive information leakage before deployment

ReadonlypropertiesinPHP8.2canonlybeassignedonceintheconstructororatdeclarationandcannotbemodifiedafterward,enforcingimmutabilityatthelanguagelevel.2.Toachievedeepimmutability,wrapmutabletypeslikearraysinArrayObjectorusecustomimmutablecollectionssucha

Bref enables PHP developers to build scalable, cost-effective applications without managing servers. 1.Bref brings PHP to AWSLambda by providing an optimized PHP runtime layer, supports PHP8.3 and other versions, and seamlessly integrates with frameworks such as Laravel and Symfony; 2. The deployment steps include: installing Bref using Composer, configuring serverless.yml to define functions and events, such as HTTP endpoints and Artisan commands; 3. Execute serverlessdeploy command to complete the deployment, automatically configure APIGateway and generate access URLs; 4. For Lambda restrictions, Bref provides solutions.

PHP's garbage collection mechanism is based on reference counting, but circular references need to be processed by a periodic circular garbage collector; 1. Reference count releases memory immediately when there is no reference to the variable; 2. Reference reference causes memory to be unable to be automatically released, and it depends on GC to detect and clean it; 3. GC is triggered when the "possible root" zval reaches the threshold or manually calls gc_collect_cycles(); 4. Long-term running PHP applications should monitor gc_status() and call gc_collect_cycles() in time to avoid memory leakage; 5. Best practices include avoiding circular references, using gc_disable() to optimize performance key areas, and dereference objects through the ORM's clear() method.