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Property Graph Model
A graph data model where nodes and edges carry labels and key-value properties, enabling typed multi-hop traversals without joins.
2mo ago Knowledge Engineering intermediate
Python functools Module Python 3.2+
The functools module provides higher-order tools like wraps, partial, lru_cache, reduce, and singledispatch for building and reusing function logic.
3mo ago Python intermediate
Prompt Caching
API feature where a static prompt prefix (system instructions, large context) is cached server-side, dramatically reducing cost and latency on repeated calls that share the prefix.
5mo ago AI / ML intermediate
Diagram: PDO Transactions PDO Transactions PHP 5.1+ 🧠 4
PDO wraps multiple queries in an atomic unit — either all succeed or all roll back.
6mo ago PHP intermediate
PDO::ATTR_EMULATE_PREPARES PHP 5.1+
Controls whether PDO sends real prepared statements to the database or emulates them client-side in PHP.
CWE-89 OWASP A3:2021
6mo ago PHP intermediate
PDOStatement::bindParam() vs bindValue() PHP 5.1+
Two PDO methods for binding variables to placeholders — bindParam() binds by reference (evaluated at execute), bindValue() binds by value (evaluated immediately).
6mo ago PHP intermediate
PHP Generators PHP 5.5+ 🧠 1
Functions using yield that produce values lazily — one at a time — instead of building a complete array in memory.
6mo ago PHP intermediate
Permissions API HTML5
The Permissions API (navigator.permissions.query()) lets you check the current state of browser permissions — granted, denied, or prompt — before requesting sensitive APIs.
6mo ago JavaScript intermediate
Pessimistic Locking 🧠 5
Pessimistic locking acquires an exclusive lock immediately on read — preventing any concurrent modification. Right for high-contention scenarios but reduces throughput.
6mo ago Concurrency intermediate
PHP 4 Objects Passed by Value (Pre-5 Gotcha) PHP 4.0+ 🧠 1
PHP 4 copied objects on assignment — $b = $a created a full clone. PHP 5+ passes object handles by value (reference semantics). This was the biggest PHP 4 pain point.
6mo ago PHP intermediate
PHP 8 — Key Features PHP 8.0+
PHP 8.0–8.4 introduced match expressions, named arguments, union types, nullsafe operator, fibers, enums, readonly properties, first-class callables, and a JIT compiler — the most significant evolution of the language since PHP 5.
6mo ago PHP intermediate
PHP Execution Model — Shared-Nothing Architecture PHP 5.0+ 🧠 3
Each PHP request runs in a completely isolated process or thread — no memory, globals, or state is shared between requests. Every request bootstraps the entire application from scratch and discards everything when it ends.
6mo ago PHP intermediate
PHP SAPI Types (FPM, CLI, Embed) PHP 4.0+
SAPI (Server API) defines how PHP is invoked — php-fpm for web requests, php-cli for commands, embed for C extensions — each has different lifecycle and configuration.
6mo ago PHP intermediate
PHP Version Upgrade Checklist PHP 5.0+
A systematic PHP upgrade process: check EOL status, run static analysis, update Composer deps, run Rector, test on new version in staging, then deploy — never upgrade directly in production.
6mo ago PHP intermediate
Pluralisation Rules PHP 7.0+
Language-specific rules governing how word forms change based on quantity — English has two forms (1 item / 2 items), but many languages have three, four, or six distinct plural forms requiring different translations.
6mo ago i18n intermediate
Producer-Consumer Pattern
Producer-Consumer decouples work generation from processing — producers add to a queue, consumers process independently, buffering load spikes and enabling parallel throughput.
6mo ago Concurrency intermediate
Progressive Web App (PWA) 🧠 1
A web application that uses modern browser APIs to deliver app-like experiences — installable on the home screen, working offline, and receiving push notifications — without requiring an app store.
6mo ago Mobile intermediate
Prometheus Concepts
Prometheus is a pull-based metrics system — services expose /metrics in text format, Prometheus scrapes them, stores as time series, and evaluates alerting rules via PromQL.
6mo ago Observability intermediate
Promise.allSettled / Promise.any / Promise.race ES2020
Three Promise combinators for handling multiple async operations — allSettled() waits for all to complete regardless of failure, any() resolves with the first success, race() resolves or rejects with the first to settle.
6mo ago JavaScript intermediate
Promises & Futures PHP 7.0+ 🧠 4
Abstractions representing the eventual result of an async operation — a Promise or Future is a placeholder for a value not yet available, enabling non-blocking code composition without nested callbacks.
6mo ago Concurrency intermediate
✓ schema.org compliant