mysql支持mysqli

$mysqli = new mysqli("localhost", "username", "password", "database");

if ($mysqli->connect_errno) {
    echo "Failed to connect to MySQL: " . $mysqli->connect_error;
    exit();
}

$stmt = $mysqli->prepare("SELECT * FROM users WHERE username = ?");
$stmt->bind_param("s", $username);

$username = $_POST['username'];
$stmt->execute();

$result = $stmt->get_result();
while ($row = $result->fetch_assoc()) {
    // 处理结果
}

$stmt->close();
$mysqli->close();

$mysqli->begin_transaction();

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

    $mysqli->commit();
} catch (Exception $e) {
    $mysqli->rollback();
    echo "Transaction failed: " . $e->getMessage();
}