Карта знаний PHP — deepseek-flash, run-07 · think: low

{"answer": "no", "explanation": "Double-quoted strings interpolate variables and process more escape sequences, while single-quoted strings do not."}

{"answer":"yes","explanation":"The null coalescing operator suppresses undefined-variable warnings and behaves like isset()."}

{"answer":"ab","explanation":"echo outputs each argument consecutively, so 'a' and 'b' print as 'ab'."}

{"answer":"yes","explanation":"In PHP, print is an expression that returns 1, so it can be used inside expressions."}

{"answer":"no","explanation":"The elvis operator returns its left operand when it is truthy, not falsy."}

{"answer":"yes","explanation":"In PHP 8, the concatenation operator (.) has lower precedence than addition and subtraction."}

{"answer":"no","explanation":"PHP's ** operator is right-associative, so 2 ** 3 ** 2 evaluates as 2 ** (3 ** 2) = 512, not 64."}

{"answer":"sum: 5","explanation":"In PHP 8, addition has higher precedence than concatenation, so 2 + 3 is evaluated first."}

{"answer":"no","explanation":"Strict array comparison requires the same key/value pairs in the same order and of the same types."}

{"answer":"no","explanation":"In PHP, 0 == false is a loose comparison and evaluates to true, not false."}

{"answer":"no","explanation":"In PHP 8, non-numeric strings are no longer converted to 0 when compared with numbers, so \"abc\" == 0 is false."}

{"answer":"yes","explanation":"In PHP loose comparison, null == 0, null == \"\", and null == false all evaluate to true."}

{"answer": 42, "explanation": "PHP casts the leading numeric portion '42' to an integer and stops at the non-numeric character."}

{"answer": 10, "explanation": "PHP coerces the numeric string '5' to an integer, so 5 + 5 equals 10."}

{"answer":"no","explanation":"Casting false to string in PHP yields an empty string, not \"0\"."}

{"answer":"yes","explanation":"Due to floating-point precision, 0.1 + 0.2 is not exactly equal to 0.3, so the strict comparison returns false."}

{"answer": "no", "explanation": "strrev() reverses bytes, so it does not correctly reverse multibyte UTF-8 characters."}

{"answer":"yes","explanation":"The substring 'world' occurs in 'Hello world', so str_contains returns true."}

{"answer":"no","explanation":"str_pad() supports STR_PAD_LEFT, STR_PAD_RIGHT, and STR_PAD_BOTH."}

{"answer":"no","explanation":"By default trim() strips spaces, tabs, newlines, carriage returns, NUL bytes, and vertical tabs."}

{"answer": 6, "explanation": "strlen() counts bytes, and é is two bytes in UTF-8, so h(1)+é(2)+l+l+o = 6."}

{"answer":"def","explanation":"A negative start counts from the end of the string, so it returns the last three characters."}

{"answer": "no", "explanation": "ucfirst() returns a new string and does not modify the original argument in place."}

{"answer": "yes", "explanation": "Heredoc interpolates variables, while nowdoc does not."}

{"answer": "no", "explanation": "sort() reindexes the array numerically and does not preserve key-to-value associations."}

{"answer": "yes", "explanation": "PHP casts numeric string array keys like '5' to integer keys."}

{"answer":"no","explanation":"By default in_array() uses loose comparison; strict comparison requires passing true as the third argument."}

{"answer": "yes", "explanation": "Without a callback, array_filter() keeps only elements that are truthy, removing all falsy values."}

{"answer":"no","explanation":"By default array_slice() reindexes numeric keys; it preserves them only when preserve_keys is true."}

{"answer":"[20, 30]","explanation":"array_slice returns the two elements starting at index 1, namely 20 and 30."}

{"answer": 2, "explanation": "The union operator keeps the left array's 'a' key and adds 'b', resulting in two elements."}

{"answer":"yes","explanation":"PHP 8.1 added support for unpacking arrays with string keys using the spread operator."}

{"answer":"no","explanation":"PHP allows named arguments to be combined with argument unpacking in a single call, subject to ordering rules."}

{"answer":"no","explanation":"PHP closures do not capture outer-scope variables unless they are explicitly imported with use."}

{"answer": 3, "explanation": "func_num_args() returns the total number of arguments passed to the function, including those beyond declared parameters."}

{"answer":"no","explanation":"PHP arrow functions can only contain a single expression, not a brace-delimited block of multiple expressions."}

{"answer":"no","explanation":"PHP arrow functions capture outer variables by value automatically, not by reference."}

{"answer":"yes","explanation":"A static closure cannot be bound to an object, so it does not capture $this."}

{"answer": 5, "explanation": "The closure captures $x by value at definition time, so it retains 5."}

{"answer": "yes", "explanation": "In weak typing mode, PHP coerces numeric strings like \"5\" to int for int parameters."}

{"answer":"yes","explanation":"Constructor property promotion was introduced in PHP 8.0 and allows declaring properties directly in the constructor parameters."}

{"answer": "final", "explanation": "Declaring a method final prevents subclasses from overriding it."}

{"answer":"yes","explanation":"In PHP, a final method cannot be overridden by a subclass."}

{"answer": "no", "explanation": "Private parent properties are not accessible in a subclass."}

{"answer":"class@anonymous","explanation":"PHP names anonymous classes with a generated name whose portion before the NUL byte is \"class@anonymous\"."}

{"answer":"yes","explanation":"Private methods are not inherited, so a child can declare a same-named method with any visibility."}

{"answer":"no","explanation":"__get() is also invoked when reading inaccessible (protected or private) properties, not only non-existent ones."}

{"answer": "Error", "explanation": "Reassigning an initialized readonly property throws an Error, not an Exception."}

{"answer": "yes", "explanation": "PHP interfaces may declare constants, which implementing classes inherit."}

{"answer":"instanceof","explanation":"The instanceof operator checks if an object is an instance of a class or interface."}

{"answer":"yes","explanation":"PHP interfaces can declare static methods, which implementing classes must define as static."}

{"answer": "no", "explanation": "The instanceof operator also returns true for implemented interfaces, not just class inheritance."}

{"answer":"no","explanation":"PHP interfaces only declare method signatures and cannot provide default implementations."}

{"answer": "yes", "explanation": "PHP allows abstract methods in abstract classes to have public or protected visibility, but not private."}

{"answer": 3, "explanation": "Foo::cases() returns an array containing all three enum cases."}

{"answer":"yes","explanation":"As of PHP 8.2, traits can declare constants."}

{"answer":"yes","explanation":"In PHP, Throwable is the base interface implemented by both Exception and Error."}

{"answer": "no", "explanation": "TypeError extends Error, not Exception, so a catch (Exception $e) block will not catch it."}

{"answer": "no", "explanation": "The @ operator suppresses error messages, not exceptions."}

{"answer":"DivisionByZeroError","explanation":"intdiv() with a zero divisor throws a DivisionByZeroError in PHP."}

{"answer": "no", "explanation": "A finally block always runs, even if the exception is not caught."}

{"answer": "no", "explanation": "An exception thrown in a finally block overrides any exception or return value from the try block, so it does affect the result."}

{"answer": "yes", "explanation": "Casting any object to bool in PHP yields true."}

{"answer":"yes","explanation":"Registered shutdown functions are executed when the script terminates, including when exit() or die() is called."}

{"answer":"no","explanation":"A use statement only imports/aliases a name; it does not autoload or include the class file."}

{"answer": "function", "explanation": "In PHP, functions are imported with the `use function` statement, while `use const` imports constants."}

{"answer": "Controller/Api/UserController.php", "explanation": "The PSR-4 prefix App\\ maps to src/, so the remaining namespace becomes the subpath plus .php."}

{"answer":"yes","explanation":"Composer's vendor/autoload.php initializes and registers the generated autoloader with spl_autoload_register()."}

{"answer":"yes","explanation":"In PHP, __NAMESPACE__ evaluates to the name of the current namespace as a string."}

{"answer": "no", "explanation": "In a namespace, an unqualified class name in new resolves relative to the current namespace, not the global root."}

{"answer": "yes", "explanation": "Under PSR-4, the namespace prefix App\\ maps to src/, so App\\Model\\User corresponds to src/Model/User.php."}

{"answer":"no","explanation":"PHP namespace/class imports via use must be at the outermost scope, so block-scoped importing inside a function is not supported."}

{"answer": "yes", "explanation": "PHP arrays have value semantics, so assignment copies the array (using copy-on-write) rather than passing it by reference."}

{"answer": 2, "explanation": "PHP arrays are assigned by value, so appending to $b does not change $a."}

{"answer":"yes","explanation":"PHP functions have local scope, so global variables require global, $GLOBALS, or parameters to be accessed."}

{"answer":"no","explanation":"Unsetting $GLOBALS['x'] removes the global variable from the global scope, not just within the function."}

{"answer": 6, "explanation": "The parameter is passed by reference, so inc() increments $n to 6."}

{"answer":"no","explanation":"A foreach by value iterates over a copy, so changes to the array inside the loop are not visible in the same pass."}

{"answer": "no", "explanation": "Static properties belong to the class and are shared across all instances, so changes are visible in other objects."}

{"answer": "no", "explanation": "Boolean array keys are cast to integers in PHP, so true becomes 1, not a boolean key."}

{"answer": "yes", "explanation": "A generator can return a value, which is retrieved with getReturn() after iteration completes."}

{"answer": "no", "explanation": "A PHP generator cannot be rewound after it has started or been fully consumed; calling rewind() then throws an exception."}

{"answer":"yes","explanation":"PHP's yield from delegates iteration to another generator or iterable."}

{"answer":"Generator","explanation":"A function containing yield returns a Generator object, so get_class() reports its class name."}

{"answer": 3, "explanation": "The generator yields the three elements 1, 2, and 3, so iterator_to_array produces an array with 3 elements."}

{"answer":"no","explanation":"SplStack is a LIFO stack, not a FIFO queue."}

{"answer":"yes","explanation":"ArrayIterator implements Iterator and can wrap an array for traversal."}

{"answer": "no", "explanation": "ArrayObject implements IteratorAggregate, so it can be traversed with foreach."}

{"answer": "yes", "explanation": "password_hash() automatically generates a secure salt, so you do not need to provide one separately."}

{"answer":"no","explanation":"PASSWORD_DEFAULT uses bcrypt (not MD5) and handles salting automatically."}

{"answer": "yes", "explanation": "password_verify returns true when the plaintext password matches the stored hash."}

{"answer":"no","explanation":"strip_tags() removes HTML/PHP tags and does not prevent SQL injection, which requires proper escaping or prepared statements."}

{"answer":"yes","explanation":"Regenerating the session ID on login prevents session fixation by giving the authenticated session a new ID."}

{"answer":"php_sapi_name","explanation":"php_sapi_name() returns the current Server API name, such as cli."}

{"answer": "yes", "explanation": "session_destroy() removes server-side session data but does not delete the session cookie from the browser."}

{"answer":"no","explanation":"Session data is only populated after session_start() is called (or session auto-start is enabled)."}

{"answer": "8.4", "explanation": "The array_find() function was introduced in PHP 8.4."}

{"answer": "yes", "explanation": "Property hooks were introduced in PHP 8.4, allowing get and set logic directly in property declarations."}

{"answer": "yes", "explanation": "PHP 8.4 introduced asymmetric property visibility, such as public private(set) string $name."}

{"answer":"8.5","explanation":"The #[\NoDiscard] attribute was introduced in PHP 8.5."}

{"answer":"8.5","explanation":"The pipe operator |> was introduced in PHP 8.5."}

{"answer":"8.5","explanation":"The clone-with syntax was introduced in PHP 8.5."}

{"answer": "8.5", "explanation": "The array_first() and array_last() functions were introduced in PHP 8.5."}

{"answer":"8.6","explanation":"RFC Partial Function Application v2 was adopted for PHP 8.6."}

{"answer":"8.5","explanation":"The clamp_v2 RFC was implemented in PHP 8.5."}

{"answer":"no","explanation":"No PHP RFC named Context Managers v2 has been adopted; the stated date is also in the future."}

{"answer":"yes","explanation":"The Bound-Erased Generic Types RFC was declined in 2026."}

{"answer":"no","explanation":"No PHP RFC making ZTS (thread safety) the default build has been accepted as of 2026-11-07."}

{"answer":"yes","explanation":"PHP 8.5 still does not support native generics/parameterized types."}

{"answer":"yes","explanation":"PHP 8.6's GA date is after 2026-11-07, so the latest stable release on that date is PHP 8.5."}

{"answer":"yes","explanation":"PHP 6 was developed but never released, and PHP 7.0 followed PHP 5.6."}

{"answer":"yes","explanation":"The RFC for the core #[\Deprecated] attribute was adopted and implemented in PHP 8.4."}

{"answer": "yes", "explanation": "In clean and onion architecture, dependencies point inward, so inner layers know nothing about outer layers."}

{"answer": "yes", "explanation": "Domain entities should remain framework-agnostic, depending only on the language and possibly the standard library."}

{"answer": "no", "explanation": "Controllers and Twig templates belong to the presentation/interface layer, not the business-logic layer, even if controllers invoke use cases."}

{"answer": "The domain model", "explanation": "In onion architecture, the domain model (entities/business rules) sits at the center, with dependencies pointing inward."}

{"answer": "yes", "explanation": "Tools like deptrac statically analyze dependencies and can fail builds when a forbidden layer call is detected."}

{"answer":"no","explanation":"Use cases should not depend on framework-specific HTTP requests or ORM EntityManagers; that couples business logic to infrastructure."}

{"answer": "Repository", "explanation": "A repository provides collection-like access to aggregates while encapsulating persistence behind an interface."}

{"answer":"yes","explanation":"In clean architecture, database details belong to the outer layer, so replacing PostgreSQL should not affect domain or use-case code."}

{"answer": "no", "explanation": "An aggregate is a consistency boundary around domain objects, not a database table."}

{"answer": "yes", "explanation": "Value Objects are immutable and equality is based on their field values rather than object identity."}

{"answer": "aggregate root", "explanation": "In domain-driven design, the aggregate root is the only external entry point through which all changes to an aggregate must pass."}

{"answer": "yes", "explanation": "A repository is defined for an aggregate root, not for every entity within the aggregate."}

{"answer":"yes","explanation":"Ubiquitous language is a shared domain language used by developers and domain experts."}

{"answer":"universe of discourse","explanation":"The boundary within which a model and its language remain consistent is called the universe of discourse."}

{"answer": "no", "explanation": "DDD recommends rich domain models, not anemic ones with logic in services."}

{"answer": "yes", "explanation": "A bounded context defines a model boundary, so the same real-world concept can be modeled as distinct classes in different contexts."}

{"answer":"no","explanation":"Symfony services are not lazy by default; they are instantiated when fetched from the container unless marked lazy."}

{"answer": "debug:router", "explanation": "The Symfony console command debug:router lists all registered routes."}

{"answer": "no", "explanation": "Symfony autowiring lets services be registered automatically via resource loading and autoconfigure, so you don't need to declare every service manually."}

{"answer":"yes","explanation":"Twig compiles templates into PHP classes and caches them between requests."}

{"answer": "yes", "explanation": "Symfony caches the dev container and rebuilds it only when tracked resource files change, not on every request."}

{"answer":"APP_ENV","explanation":"Symfony reads the active environment from the APP_ENV environment variable."}

{"answer":"no","explanation":"Symfony controller methods used by routes must be public; private methods are not callable by the controller resolver."}

{"answer": "no", "explanation": "Event subscribers are not automatically prioritized over listeners; ordering depends on registered priority values."}

{"answer":"yes","explanation":"Symfony 6.0 removed the old Guard authentication system in favor of authenticator classes implementing AuthenticatorInterface."}

{"answer":"IsGranted","explanation":"The #[IsGranted] attribute enforces role or permission checks on a controller method and returns 403 if not granted."}

{"answer":"yes","explanation":"Symfony voters are used by isGranted() to decide whether access to a specific object is granted."}

{"answer": "yes", "explanation": "Symfony 7 removed support for Doctrine-style annotations, so validation constraints must use PHP attributes."}

{"answer": "yes", "explanation": "Symfony forms enable CSRF protection by default and validate the token on submission."}

{"answer": "yes", "explanation": "Symfony form validation always runs server-side; HTML5 client checks are only a convenience and can be bypassed."}

{"answer":"make:form","explanation":"The Symfony MakerBundle command make:form generates a FormType class."}

{"answer": "no", "explanation": "Symfony does not store the user's plain-text password in the session; authentication state is tracked without exposing the password."}

{"answer":"yes","explanation":"Symfony recommends placing bundle configuration in config/packages, typically with one file per bundle or topic."}

{"answer": "yes", "explanation": "This matches Symfony's convention: .env is committed with defaults, while .env.local is ignored and holds local secrets."}

{"answer":"debug:container","explanation":"The debug:container command lists registered services and their aliases in the Symfony container."}

{"answer": "no", "explanation": "In a compiled Symfony container, parameters are immutable, so setParameter() throws a LogicException at runtime."}

{"answer": "no", "explanation": "By default, Symfony services are private, not public, so they cannot be fetched directly from the container."}

{"answer": "no", "explanation": "Bundles can work with default configuration and do not require a config file in config/packages."}

{"answer": "yes", "explanation": "Symfony supports referencing environment variables in services.yaml using the %env(VAR)% syntax."}

{"answer":"APP_DEBUG","explanation":"Symfony uses the APP_DEBUG environment variable to enable debug mode, which activates the profiler and Twig debugging."}

{"answer":"no","explanation":"Symfony Messenger allows multiple handlers for the same message, and all matching handlers are called."}

{"answer": "no", "explanation": "The sync transport handles the message immediately in the current process, unlike async transports that queue messages for a worker."}

{"answer":"messenger:consume","explanation":"The Symfony Messenger worker is started with the messenger:consume command."}

{"answer":"yes","explanation":"In Symfony Messenger, retry_strategy is configured per transport under the messenger transports configuration."}

{"answer": "no", "explanation": "Symfony Messenger uses the PHP serializer by default, not JSON."}

{"answer": "yes", "explanation": "Symfony Scheduler generates messages according to a schedule and dispatches them via Messenger."}

{"answer": "Doctrine", "explanation": "The Doctrine transport stores Messenger messages in database tables via Doctrine DBAL."}

{"answer": "yes", "explanation": "Symfony Messenger allows custom middleware to be added to the bus middleware chain, including before or after built-in middleware."}

{"answer":"yes","explanation":"Symfony follows a two-year major release cycle and six-month minor releases in May and November."}

{"answer":"8.4","explanation":"Symfony 8 requires PHP 8.4 as its minimum supported version."}

{"answer":"no","explanation":"Symfony 7.0 removed support for docblock annotations; attributes are required."}

{"answer": "yes", "explanation": "Symfony's AssetMapper uses importmap.php to manage CSS/JS assets without requiring Node.js or Webpack."}

{"answer":"no","explanation":"Symfony 6.4 is a long-term support (LTS) release, not a regular release."}

{"answer": "no", "explanation": "Symfony major releases remove deprecations introduced in the previous major branch, so they do not keep working."}

{"answer":"yes","explanation":"Symfony publishes UPGRADE guides for each major release documenting backward-incompatible changes."}

{"answer": "AssetMapper", "explanation": "Symfony's AssetMapper component manages assets and importmaps without Node.js or Webpack."}

{"answer":"no","explanation":"Symfony 8.2 is scheduled for release in November 2026, typically late in the month, so it would not yet be released on 2026-11-07."}

{"answer":"yes","explanation":"Symfony follows a six-month minor release cycle, so after 8.0 in November 2025 and 8.1 in May 2026, 8.2 is scheduled for November 2026."}

{"answer":"8.2","explanation":"Symfony follows a six-month minor release cycle, so the release after 8.1 is 8.2."}

{"answer": "no", "explanation": "Symfony 8.2 would be a minor release, not a major release requiring applications to be rewritten."}

{"answer":"yes","explanation":"PHP minor releases generally preserve backward compatibility, though deprecations may encourage future changes."}

{"answer":"8.4","explanation":"Symfony 8.4 is the final minor release in the 8.x branch before Symfony 9.0."}

{"answer":"no","explanation":"Symfony minor releases generally keep the same PHP requirement as the major release, so Symfony 8.2 is expected to require PHP 8.4, not PHP 8.5."}

{"answer": "yes", "explanation": "Symfony deprecations introduced in 8.x are only removed in the next major version, 9.0."}

{"answer": "no", "explanation": "Twig expressions cannot call arbitrary PHP directly; only exposed functions, filters, and variables are available."}

{"answer":"yes","explanation":"Twig enables autoescaping by default, escaping printed variables for HTML context."}

{"answer": "yes", "explanation": "Twig's |e filter escapes output for HTML by default, making it safe in HTML contexts."}

{"answer":"format_number","explanation":"The format_number filter formats a number according to the given locale."}

{"answer":"yes","explanation":"The |raw filter marks a value as safe so Twig does not auto-escape it."}

{"answer": "yes", "explanation": "Twig uses {{ }} for outputting expression values and {% %} for executing tags such as conditions, loops, and assignments."}

{"answer": "no", "explanation": "Twig allows declaring variables in templates using the set tag, not only via the controller."}

{"answer": "dump", "explanation": "Twig's dump() function outputs the debug structure of a variable when debug is enabled."}

{"answer":"yes","explanation":"Bootstrap provides ready-made CSS and JavaScript UI components and is not a single-page application framework."}

{"answer": "container", "explanation": "Bootstrap's .container sets a responsive fixed max-width at each breakpoint."}

{"answer":"no","explanation":"Bootstrap's grid uses 12 columns, not 16, and newer versions use flexbox rather than floats."}

{"answer": "yes", "explanation": "Bootstrap 5 defines five named breakpoint infixes: sm, md, lg, xl, and xxl."}

{"answer":"yes","explanation":"Bootstrap's spacing utilities map each number to a value in the $spacers scale, which is defined as multiples (or fractions) of $spacer."}

{"answer": "data-bs-toggle", "explanation": "Bootstrap 5 uses data-bs-toggle to initialize interactive components like dropdowns."}

{"answer": "yes", "explanation": "Bootstrap 5 components are implemented in vanilla JavaScript and do not require jQuery."}

{"answer":"no","explanation":"Bootstrap 5.3 enables dark mode with the data-bs-theme=\"dark\" attribute on the root element, not a .dark class."}

{"answer":"no","explanation":"Doctrine ORM does not create tables automatically at runtime; schema creation is done explicitly via tools or migrations."}

{"answer": "persist", "explanation": "EntityManager::persist() schedules a new entity for insertion and defers SQL until flush()."}

{"answer": "no", "explanation": "EntityManager::merge() was deprecated in Doctrine ORM 2.x and removed in ORM 3.0."}

{"answer":"yes","explanation":"DQL is written using entity names and their mapped fields rather than database table and column names."}

{"answer": "null", "explanation": "Doctrine's find() returns null when no matching record exists."}

{"answer":"no","explanation":"DoctrineBundle does not automatically call flush() at the end of each request; you must flush explicitly."}

{"answer": "yes", "explanation": "Doctrine's Unit of Work tracks changes to managed entities, so flush() updates them without an explicit persist()."}

{"answer": "no", "explanation": "remove() only marks the entity for deletion; the SQL DELETE is executed on flush()."}

{"answer":"no","explanation":"PostgreSQL's MVCC allows readers and writers to operate concurrently without blocking each other."}

{"answer": "EXPLAIN", "explanation": "EXPLAIN displays the execution plan without running the query (in databases like MySQL and PostgreSQL)."}

{"answer":"no","explanation":"SERIAL is a PostgreSQL pseudo-type using a sequence default, while GENERATED ... AS IDENTITY is the SQL-standard identity mechanism with different semantics."}

{"answer": "no", "explanation": "By default PostgreSQL UNIQUE constraints treat NULLs as distinct, so multiple rows with NULL are allowed."}

{"answer":"string_agg","explanation":"PostgreSQL's string_agg aggregate concatenates string values using a specified separator."}

{"answer":"no","explanation":"Plain VACUUM marks space from dead tuples as reusable inside the database but does not return it to the operating system; VACUUM FULL does."}

{"answer": "PARTITION BY", "explanation": "The PARTITION BY clause divides rows into groups over which the window function is computed."}

{"answer":"no","explanation":"READ COMMITTED prevents dirty reads but allows non-repeatable reads because each statement sees a new snapshot."}

{"answer": "yes", "explanation": "PostgreSQL runs each SQL statement in its own implicit transaction unless you explicitly start a transaction block."}

{"answer": "COMMIT", "explanation": "The COMMIT command permanently saves all changes made during the current transaction."}

{"answer":"yes","explanation":"Indexes can also speed up UPDATE and DELETE statements that use an indexed column in their search condition."}

{"answer": "yes", "explanation": "PostgreSQL uses SAVEPOINT to roll back part of a transaction to a marked point."}

{"answer": "no", "explanation": "EXPLAIN ANALYZE actually executes the query and reports runtime statistics."}

{"answer":"pgvector","explanation":"The pgvector extension adds vector data types and vector indexes for embedding similarity search in PostgreSQL."}

{"answer": "yes", "explanation": "A partial index includes only table rows that satisfy its WHERE predicate."}

{"answer": "no", "explanation": "PostgreSQL implements SERIALIZABLE using Serializable Snapshot Isolation with predicate locks, not by locking the rows a transaction reads."}

{"answer":"yes","explanation":"HTTP 201 Created indicates that the request successfully resulted in a new resource being created."}

{"answer": 204, "explanation": "HTTP 204 No Content indicates a successful request with no response body."}

{"answer": "yes", "explanation": "DELETE is idempotent because repeating the same request leaves the resource in the same final state."}

{"answer": "no", "explanation": "The Access-Control-Allow-Origin header is sent by the server, not the client, to indicate allowed origins."}

{"answer":"yes","explanation":"HTTP 429 Too Many Requests indicates the client has exceeded a rate limit."}

{"answer":"no","explanation":"It is the reverse: 4xx codes indicate client errors and 5xx codes indicate server-side errors."}

{"answer": "Content-Type", "explanation": "The Content-Type header specifies the MIME type of the request or response body."}

{"answer": "yes", "explanation": "RFC 5789 states PATCH is not necessarily idempotent, whereas PUT is idempotent."}

{"answer": "no", "explanation": "Use hash_equals for constant-time comparison, since == is vulnerable to timing attacks and type juggling."}

{"answer":"yes","explanation":"CSRF tokens are typically session-bound and checked server-side for state-changing requests such as POST."}

{"answer":"Content-Security-Policy","explanation":"The CSP policy is delivered via the Content-Security-Policy HTTP response header."}

{"answer": "no", "explanation": "OAuth 2.0 is an authorization framework, and an access token grants access rather than identifying the user."}

{"answer":"no","explanation":"XSS is prevented mainly by escaping output at render time, not by validating input before database storage."}

{"answer":"code","explanation":"The authorization server redirects back with an authorization code that the client exchanges for an access token."}

{"answer":"yes","explanation":"Refresh tokens are long-lived credentials used to obtain new access tokens without requiring the user to log in again."}

{"answer": "no", "explanation": "A salt does not need to be secret; it is stored alongside the hash and is required to verify it, but secrecy is not required."}

{"answer":"no","explanation":"PHPUnit test classes must extend PHPUnit\\Framework\\TestCase (or implement the Test interface) for its test methods to be discovered and run."}

{"answer":"no","explanation":"setUp() runs before each test method, while setUpBeforeClass() runs once before all tests."}

{"answer": "no", "explanation": "A data provider can supply multiple sets of arguments, causing the test to run once per set."}

{"answer":"expectException","explanation":"PHPUnit's expectException() method declares that a specified exception class is expected to be thrown."}

{"answer": "no", "explanation": "It is reversed: stubs return canned data, while mocks can verify method calls and expectations."}

{"answer":"yes","explanation":"PHPUnit 10+ recommends the #[DataProvider] attribute, while the @dataProvider annotation is deprecated."}

{"answer":"no","explanation":"PHPUnit allows tests to depend on other tests using the @depends annotation."}

{"answer":"--order-by=random","explanation":"PHPUnit's --order-by=random option runs tests in a random order."}

{"answer":"3-3","explanation":"intdiv(7,2) is 3 and intdiv(-7,2) is -3, so concatenation produces \"3-3\"."}

{"answer": -9, "explanation": "In PHP, exponentiation has higher precedence than unary minus, so it evaluates as -(3 ** 2) = -9."}

{"answer":"true","explanation":"Both strings are numeric, so PHP compares them numerically: 1e1 equals 10."}

{"answer":"other","explanation":"In PHP 8, 'a' does not loosely equal 0, so the default branch runs and prints 'other'."}

{"answer":"2c","explanation":"strtr() with an array replaces the longest matching substring first, so 'ab' becomes '2' and 'c' remains."}

{"answer":"[hello]","explanation":"A negative start beyond the string length is treated as 0, so substr returns the whole string."}

{"answer":"k,n,m","explanation":"The array union preserves keys from the left array and adds non-conflicting keys from the right, so array_keys() returns k, n, m."}

{"answer":"yxz","explanation":"Sorting by the third element puts 'y' first, then the two equal-key elements 'x' and 'z' in stable order."}

{"answer": 4, "explanation": "The associative array is unpacked as named arguments, so $a=5 and $b=1, returning 4."}

{"answer": 3, "explanation": "The first-class callable closure keeps the object alive and calls g(), returning the private property value 3."}

{"answer":"B","explanation":"static::class uses late static binding, so it resolves to the runtime class B."}

{"answer": 10, "explanation": "The set hook writes $value * 2 (5 * 2) to the property's backing value, so reading $c->x returns 10."}

{"answer":"BA","explanation":"TB::f is used as f and TA::f is aliased to g, so concatenating returns 'B' . 'A' = 'BA'."}

{"answer": 0, "explanation": "Each class using the trait gets its own separate copy of the static property, so CY::$n remains 0."}

{"answer": 2, "explanation": "A return in the finally block overrides the return value from the try block."}

{"answer":"second","explanation":"The LogicException thrown in the finally block overrides the RuntimeException and is caught by the outer catch, so getMessage() outputs \"second\"."}

{"answer":"App\\Foo|Baz","explanation":"The imported alias Baz resolves to App\\Foo, while \\Baz::class is the fully qualified global name Baz."}

{"answer":"noyes","explanation":"class_exists('Foo') checks the global Foo class, while class_exists('Ns\\Foo') finds the namespaced class."}

{"answer":"1,2,99","explanation":"After the by-reference foreach, $v still references the last element, so assigning 99 changes $a[2]."}

{"answer":3,"explanation":"In PHP 8.1+ the inherited method shares its static $n between A and B, so the three calls increment it to 3."}

{"answer":11,"explanation":"send(10) resumes the generator, assigns 10 to $x, and the generator returns 11."}

{"answer":"1,2,ok","explanation":"The inner generator yields 1 and 2, returns 'ok' to the yield from expression, and outer then yields 'ok' as the third value."}

{"answer":"noyes","explanation":"The first check matches cost 4 so it prints 'no', while the second sees cost 5 and prints 'yes', concatenating to 'noyes'."}

{"answer":"strict-out","explanation":"In PHP 8.5, E_ALL no longer includes the deprecated E_STRICT bit (2048), so the bitwise AND is 0 and the ternary prints 'strict-out'."}

{"answer":"mapped","explanation":"The HTTP_X_TOKEN server header is exposed as X-Token by Symfony and retrieved successfully."}

{"answer":"BCA","explanation":"Listeners run in descending priority: B (10), C (5), then A (0)."}

{"answer":"same","explanation":"Doctrine's identity map returns the same managed entity instance for the same ID."}

{"answer": 0, "explanation": "Persisting then removing the new entity before flush cancels the pending insert, so the users table remains empty."}

{"answer": 1, "explanation": "COUNT(x) counts only non-NULL values, so the NULL row is ignored."}

{"answer":"10,30,60","explanation":"The window sum is cumulative (10, 30, 60), and string_agg concatenates them in id order."}

{"answer":"M1M2","explanation":"The middleware are executed in the order provided, so M1 echoes before M2."}

{"answer": 11, "explanation": "Both handlers are invoked for the dispatched message, so $n becomes 1 + 10 = 11."}

{"answer": 1, "explanation": "The second insert conflicts with the unique index and is skipped, leaving one row."}

{"answer": 2, "explanation": "The unique constraint is deferred, so the duplicate insert is allowed and the SELECT counts both rows before any constraint check."}

{"answer":6,"explanation":"The filter matches both test_sum and test_sum_abs, each with 3 data provider cases, totaling 6 tests."}

{"answer":"1, 1","explanation":"PHPUnit 10.5 requires data provider methods to be static, so the invalid provider causes one test to be reported as errored/failed."}

{"answer": "POST", "explanation": "curl sends a POST request when data is provided with -d."}

{"answer": "GET", "explanation": "The -G option makes curl append the -d data as a query string and send a GET request."}

{"answer": "invalid_client", "explanation": "RFC 6749 specifies that an unknown client_id at the token endpoint results in the invalid_client error."}

{"answer": "fragment", "explanation": "With response_type=token, the access token is returned in the URI fragment of the redirect_uri."}

{"answer": 6, "explanation": "The default filter treats false as empty, so it returns 2, and 2 * 3 equals 6."}

{"answer":"Twig\\Error\\RuntimeError","explanation":"The expression parses as ('a' ~ 1) + 2, causing a PHP TypeError during rendering that Twig wraps in a RuntimeError."}

{"answer":"UnexpectedTypeException","explanation":"NotBlank cannot validate an array, so Symfony throws an UnexpectedTypeException before any count is echoed."}

{"answer":"Symfony\\Component\\Form\\Exception\\LogicException","explanation":"Calling isValid() on an unsubmitted form throws a Symfony Form LogicException."}

{"answer":"same","explanation":"Services are shared by default, so both get('a') calls return the same object instance."}

{"answer":"hi Bob!","explanation":"Compiling the container resolves nested parameter placeholders, so %greeting% becomes hi %name% and then hi Bob."}

{"answer": "960px", "explanation": "At the lg breakpoint (992px), Bootstrap 5.3's .container has a max-width of 960px."}

{"answer":"text-danger","explanation":"Both utilities have equal specificity, so the later-generated .text-danger rule overrides .text-primary in Bootstrap 5.3."}

{"answer": 2, "explanation": "The Domain class depends on both Application and Infrastructure classes, violating Domain → Domain only."}

{"answer": 3, "explanation": "BillingService in Domain depends on one Application class and two Infrastructure classes, each violating the Domain → Domain only rule."}

{"answer":"10,15","explanation":"The original Money object remains 10, while add() returns a new Money object with amount 15."}

{"answer": 1, "explanation": "The exception is thrown before unsetting the only item, so count() remains 1."}

{"answer":"hi","explanation":"PHP 8.4+ allows dereferencing `new C()` without extra parentheses, so `hi()` returns and echoes 'hi'."}

{"answer":"yesno","explanation":"The lazy ghost starts uninitialized, so the first check prints 'yes'; accessing $o->v triggers initialization, so the second check prints 'no'."}

{"answer":"no","explanation":"The Security Guard component and its AbstractGuardAuthenticator class were removed in Symfony 6.0, so they do not exist in Symfony 8.1."}

{"answer":"noyes","explanation":"AnnotationClassLoader was removed after Symfony 6.4, while AttributeClassLoader exists, so the two echoes print \"no\" then \"yes\"."}