PHP连接Mysql方式
MySQLi extension ("i" 意为 improved)
PDO (PHP Data Objects)
PDO 应用在 12 种不同数据库中， MySQLi 只针对 MySQL 数据库。
phpinfo() 查看是否安装PDO
php代码
连接数据库
<?php //MySQLi - 面向对象 $servername = "localhost"; $username = "root"; $password = "root"; // 创建连接 $conn = new mysqli($servername, $username, $password); // 检测连接 if ($conn->connect_error) { die("连接失败: " . $conn->connect_error); } echo "连接成功"; //MySQLi - 面向过程 // 创建连接 $conn = mysqli_connect($servername, $username, $password); // 检测连接 if (!$conn) { die("Connection failed: " . mysqli_connect_error()); } echo "连接成功"; //PDO try { $conn = new PDO("mysql:host=$servername;", $username, $password); echo "连接成功"; } catch (PDOException $e) { echo $e->getMessage(); } /*关闭对象*/ //MySQLi - 面向对象 $conn->close(); //MySQLi - 面向过程 mysqli_close($conn); //PDO $conn = null;
PDO增删改查
<?php $host = '127.0.0.1'; $db = 'autumn'; $user = 'root'; $pass = 'root'; $charset = 'utf8mb4'; $dsn = "mysql:host=$host;dbname=$db;charset=$charset"; $options = [ PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION, PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC, PDO::ATTR_EMULATE_PREPARES => false, ]; try { $pdo = new PDO($dsn, $user, $pass, $options); } catch (\PDOException $e) { throw new \PDOException($e->getMessage(), (int)$e->getCode()); } // Create function createUser($name) { global $pdo; $sql = "INSERT INTO user (name) VALUES (?)"; $stmt= $pdo->prepare($sql); $stmt->execute([$name]); echo "User Created\n"; } // Read function getUser($id) { global $pdo; $sql = "SELECT * FROM user WHERE id = ?"; $stmt = $pdo->prepare($sql); $stmt->execute([$id]); $user = $stmt->fetch(); print_r($user); } // Update function updateUser($id, $name) { global $pdo; $sql = "UPDATE user SET name = ? WHERE id = ?"; $stmt= $pdo->prepare($sql); $stmt->execute([$name, $id]); echo "User Updated\n"; } // Delete function deleteUser($id) { global $pdo; $sql = "DELETE FROM user WHERE id = ?"; $stmt= $pdo->prepare($sql); $stmt->execute([$id]); echo "User Deleted\n"; } // 使用示例 createUser('John Doe'); getUser(1); updateUser(1, 'Jane Doe'); deleteUser(1); ?>
