mysql 事务设置php

try {
    // 创建PDO连接
    $pdo = new PDO('mysql:host=localhost;dbname=test', 'username', 'password');

    // 开始事务
    $pdo->beginTransaction();

    // 执行SQL语句
    $pdo->exec("UPDATE accounts SET balance = balance - 100 WHERE id = 1");
    $pdo->exec("UPDATE accounts SET balance = balance + 100 WHERE id = 2");

    // 提交事务
    $pdo->commit();
} catch (Exception $e) {
    // 回滚事务
    $pdo->rollBack();
    echo "Transaction failed: " . $e->getMessage();
}

// 创建MySQLi连接
$mysqli = new mysqli('localhost', 'username', 'password', 'test');

// 检查连接
if ($mysqli->connect_error) {
    die('Connect Error (' . $mysqli->connect_errno . ') ' . $mysqli->connect_error);
}

// 开始事务
$mysqli->begin_transaction();

try {
    // 执行SQL语句
    $mysqli->query("UPDATE accounts SET balance = balance - 100 WHERE id = 1");
    $mysqli->query("UPDATE accounts SET balance = balance + 100 WHERE id = 2");

    // 提交事务
    $mysqli->commit();
} catch (Exception $e) {
    // 回滚事务
    $mysqli->rollback();
    echo "Transaction failed: " . $e->getMessage();
}

$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
$pdo->exec("SET TRANSACTION ISOLATION LEVEL READ COMMITTED");