Glossary
PDO Error Handling
PHP 5.1+
PDO has three error modes — silent, warning, and exception — controlling how database errors surface.
2mo ago
php beginner
PDO Fetch Modes
PHP 5.1+
Constants controlling how PDO returns rows — as arrays, objects, or custom classes.
2mo ago
php beginner
PDO lastInsertId()
PHP 5.1+
Returns the auto-increment ID generated by the most recent INSERT statement.
2mo ago
php beginner
PDO Named Placeholders
PHP 5.1+
Named parameters (:name) in prepared statements — more readable than positional ? placeholders for queries with multiple parameters.
2mo ago
php beginner
PDO query() vs prepare()
PHP 5.1+
PDO query() executes raw SQL immediately — prepare() parameterises it. query() must never include user-controlled values.
CWE-89 OWASP A3:2021
2mo ago
php beginner
9.8
PDO Transactions
PHP 5.1+ PDO wraps multiple queries in an atomic unit — either all succeed or all roll back.
2mo 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
2mo 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).
2mo ago
php intermediate
PDOStatement::rowCount()
PHP 5.1+
Returns the number of rows affected by the last DELETE, INSERT, or UPDATE — unreliable for SELECT.
2mo ago
php beginner
PHP Generators
PHP 5.5+
Functions using yield that produce values lazily — one at a time — instead of building a complete array in memory.
2mo ago
php intermediate
SELECT FOR UPDATE
A locking read that acquires exclusive row locks — preventing other transactions from modifying selected rows until commit.
2mo ago
database advanced
Soft Delete Pattern
Marking records as deleted with a deleted_at timestamp instead of physically removing them — preserving data for auditing and recovery.
2mo ago
database intermediate
SQL Window Functions
Window functions (ROW_NUMBER, RANK, LAG, LEAD, SUM OVER) perform calculations across a set of rows related to the current row without collapsing them into a single aggregate — enabling rankings, running totals, and comparisons within result sets.
2mo ago
database intermediate
Structured Logging
PHP 8.0+
1
Emitting log entries as machine-parseable key-value pairs (JSON) rather than free-form strings — enabling filtering, aggregation, and alerting.
2mo ago
observability intermediate
Test Doubles
PHP 8.0+
Substitute objects used in tests to replace real dependencies — mocks, stubs, spies, fakes, and dummies each serve a different purpose.
2mo ago
testing intermediate
Trie (Prefix Tree)
A tree where each node represents a character — paths from root to leaf spell out keys, enabling O(m) lookup, prefix search, and autocomplete where m is key length, independent of dataset size.
2mo ago
data_structures intermediate
WebAssembly (Wasm)
A binary instruction format that runs at near-native speed in the browser and on servers — enabling C, Rust, and Go code to run alongside JavaScript without plugins.
2mo ago
frontend advanced
AI Alignment
2
The research and engineering discipline of ensuring AI systems pursue goals that are consistent with human values, intentions, and safety — not just stated objectives.
2mo ago
ai_ml advanced
AI Context Poisoning
1
An adversarial technique where malicious instructions are injected into an LLM's context window — via user input, retrieved documents, or tool results — to hijack the model's behaviour.
2mo ago
ai_ml advanced
AI Governance
7
The policies, processes, and organisational structures that ensure AI systems are developed, deployed, and monitored responsibly — covering accountability, fairness, transparency, and compliance.
2mo ago
ai_ml advanced