PHP and MySQL
Connection (PDO)
<?php
$dsn = "mysql:host=localhost;dbname=school;charset=utf8mb4";
$pdo = new PDO($dsn, "root", "", [
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION
]);
?>CRUD Operations
// CREATE
$stmt = $pdo->prepare("INSERT INTO students (name, grade) VALUES (?, ?)");
$stmt->execute(["Alice", 85]);
// READ
$students = $pdo->query("SELECT * FROM students")->fetchAll();
// UPDATE
$stmt = $pdo->prepare("UPDATE students SET grade = ? WHERE name = ?");
$stmt->execute([90, "Alice"]);
// DELETE
$stmt = $pdo->prepare("DELETE FROM students WHERE name = ?");
$stmt->execute(["Alice"]);
?>📌 Always use prepared statements!
They prevent SQL injection attacks. Never put user input directly in SQL queries.
Example
<?php
// Database CRUD Example
$dsn = "mysql:host=localhost;dbname=test;charset=utf8mb4";
try {
$pdo = new PDO($dsn, "root", "", [
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION
]);
// Create table
$pdo->exec("CREATE TABLE IF NOT EXISTS students (
id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(100),
grade INT
)");
// Insert
$stmt = $pdo->prepare("INSERT INTO students (name, grade) VALUES (?, ?)");
$stmt->execute(["Amina", 92]);
$stmt->execute(["Ibrahim", 85]);
$stmt->execute(["Chioma", 78]);
// Read
$students = $pdo->query("SELECT * FROM students")->fetchAll();
foreach ($students as $s) {
echo "{$s['name']} - Grade: {$s['grade']}
";
}
} catch (PDOException $e) {
echo "Error: " . $e->getMessage();
}
?>Lesson Nav
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PHP Course
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