php实现增删
PHP 实现数据库增删操作
数据库连接配置
使用 PDO 或 mysqli 扩展连接数据库,推荐 PDO 方式更安全:
$host = 'localhost';
$dbname = 'test_db';
$username = 'root';
$password = '';
try {
$pdo = new PDO("mysql:host=$host;dbname=$dbname", $username, $password);
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch(PDOException $e) {
die("Connection failed: " . $e->getMessage());
}
增加数据(INSERT)
使用预处理语句防止 SQL 注入:
$name = 'John Doe';
$email = 'john@example.com';
$stmt = $pdo->prepare("INSERT INTO users (name, email) VALUES (:name, :email)");
$stmt->bindParam(':name', $name);
$stmt->bindParam(':email', $email);
if($stmt->execute()) {
echo "Record inserted successfully";
} else {
echo "Error inserting record";
}
删除数据(DELETE)
通过 ID 或其他条件删除记录:
$id = 1;
$stmt = $pdo->prepare("DELETE FROM users WHERE id = :id");
$stmt->bindParam(':id', $id);
if($stmt->execute()) {
echo "Record deleted successfully";
} else {
echo "Error deleting record";
}
更新数据(UPDATE)
修改现有记录:
$id = 1;
$newEmail = 'newemail@example.com';
$stmt = $pdo->prepare("UPDATE users SET email = :email WHERE id = :id");
$stmt->bindParam(':email', $newEmail);
$stmt->bindParam(':id', $id);
if($stmt->execute()) {
echo "Record updated successfully";
} else {
echo "Error updating record";
}
查询数据(SELECT)
获取并显示数据:
$stmt = $pdo->query("SELECT id, name, email FROM users");
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
echo "ID: " . $row['id'] . " - Name: " . $row['name'] . " - Email: " . $row['email'] . "<br>";
}
安全注意事项
始终使用预处理语句处理用户输入 对敏感操作添加权限验证 重要操作记录日志 考虑使用 ORM 框架如 Laravel Eloquent 简化操作







