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.

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.

Laravel supports the use of native SQL queries, but parameter binding should be preferred to ensure safety; 1. Use DB::select() to execute SELECT queries with parameter binding to prevent SQL injection; 2. Use DB::update() to perform UPDATE operations and return the number of rows affected; 3. Use DB::insert() to insert data; 4. Use DB::delete() to delete data; 5. Use DB::statement() to execute SQL statements without result sets such as CREATE, ALTER, etc.; 6. It is recommended to use whereRaw, selectRaw and other methods in QueryBuilder to combine native expressions to improve security

JWT is an open standard for safe transmission of information. In Java, authentication and authorization can be achieved through the JJWT library. 1. Add JJWT API, Impl and Jackson dependencies; 2. Create JwtUtil tool class to generate, parse and verify tokens; 3. Write JwtFilter intercepts requests and verify BearerTokens in Authorization header; 4. Register Filter in SpringBoot to protect the specified path; 5. Provide a login interface to return JWT after verifying the user; 6. The protected interface obtains user identity and roles through parsing the token for access control, and ultimately realizes a stateless and extensible security mechanism, suitable for distributed systems.

Go generics are supported since 1.18 and are used to write generic code for type-safe. 1. The generic function PrintSlice[Tany](s[]T) can print slices of any type, such as []int or []string. 2. Through type constraint Number limits T to numeric types such as int and float, Sum[TNumber](slice[]T)T safe summation is realized. 3. The generic structure typeBox[Tany]struct{ValueT} can encapsulate any type value and be used with the NewBox[Tany](vT)*Box[T] constructor. 4. Add Set(vT) and Get()T methods to Box[T] without

json.loads() is used to parse JSON strings into Python data structures. 1. The input must be a string wrapped in double quotes and the boolean value is true/false; 2. Supports automatic conversion of null→None, object→dict, array→list, etc.; 3. It is often used to process JSON strings returned by API. For example, response_string can be directly accessed after parsing by json.loads(). When using it, you must ensure that the JSON format is correct, otherwise an exception will be thrown.