? PHP PDO with Exception Handling

? Quick Overview

PHP PDO supports powerful exception handling mechanisms that help developers catch and manage database-related errors safely using try-catch blocks.

? Key Concepts

• PDOException class
• try-catch blocks
• ERRMODE_EXCEPTION

? Syntax & Theory

By enabling exception mode in PDO, database errors throw exceptions instead of failing silently. This ensures controlled error handling and better debugging.

? Code Example

// Demonstrates PDO connection and query with exception handling
<?php
try {
$pdo = new PDO("mysql:host=localhost;dbname=testdb", "root", "");
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$stmt = $pdo->query("SELECT id, name FROM users");
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
print_r($row);
}
} catch (PDOException $e) {
echo "Database error: " . $e->getMessage();
}
?>

? Live Output / Explanation

If the database connection or query fails, the script safely displays an error message instead of crashing.

? Interactive Concept

Change the database name intentionally and observe how the exception is triggered and handled gracefully.

? Use Cases

• Secure database-driven applications
• Error logging systems
• Production-grade PHP applications