php mysqli函数的高级用法示例

以下是PHP的MySQLi函数的一些高级用法示例：

1. 预处理语句和参数绑定

$mysqli = new mysqli("localhost", "user", "password", "database");  // 检查连接 if ($mysqli->connect_error) {     die("连接失败: " . $mysqli->connect_error); }  // 预处理SQL语句 $stmt = $mysqli->prepare("INSERT INTO users (username, password) VALUES (?, ?)");  // 绑定参数 $stmt->bind_param("ss", $username, $password);  // 设置参数并执行 $username = "john_doe"; $password = "secret"; $stmt->execute();  echo "新记录插入成功";  // 关闭连接 $mysqli->close(); 

2. 使用事务

$mysqli = new mysqli("localhost", "user", "password", "database");  // 检查连接 if ($mysqli->connect_error) {     die("连接失败: " . $mysqli->connect_error); }  // 开始事务 $mysqli->begin_transaction();  try {     // 插入第一条记录     $stmt = $mysqli->prepare("INSERT INTO users (username, password) VALUES (?, ?)");     $stmt->bind_param("ss", $username1, $password1);     $username1 = "john_doe";     $password1 = "secret";     $stmt->execute();      // 插入第二条记录     $stmt = $mysqli->prepare("INSERT INTO orders (user_id, product) VALUES (?, ?)");     $stmt->bind_param("is", $userId, $product);     $userId = 1;     $product = "laptop";     $stmt->execute();      // 提交事务     $mysqli->commit(); } catch (Exception $e) {     // 发生错误，回滚事务     $mysqli->rollback();     echo "Error: " . $e->getMessage(); }  // 关闭连接 $mysqli->close(); 

3. 使用存储过程和命名参数

首先，创建一个带有命名参数的存储过程：

DELIMITER // CREATE PROCEDURE insert_user_with_name(IN p_username VARCHAR(255), IN p_password VARCHAR(255)) BEGIN     INSERT INTO users (username, password) VALUES (p_username, p_password); END // DELIMITER ; 

然后，在PHP中调用该存储过程：

$mysqli = new mysqli("localhost", "user", "password", "database");  // 检查连接 if ($mysqli->connect_error) {     die("连接失败: " . $mysqli->connect_error); }  // 调用存储过程 $username = "john_doe"; $password = "secret"; $stmt = $mysqli->prepare("CALL insert_user_with_name(?, ?)"); $stmt->bind_param("ss", $username, $password); $stmt->execute();  echo "新用户插入成功";  // 关闭连接 $mysqli->close();