PDO::query

[Rimma Bogdanova]

The first code selects the database of publications and I see in the browser "Default database is publications".
The following code must to select of data from table classics - the author column and show it to the browser. But the code does not output column authot to the browser. How to fix the situation? I have php7.2.7 with the php_pdo_mysql.dll.
What I'm doing wrong?

<?php
$mysqli = new mysqli('127.0.0.1', 'nativeuser', '123', 'publications');
if (mysqli_connect_errno()) {
printf("Connect failed: %s\n", mysqli_connect_error());
exit();}
if ($result = $mysqli->query("SELECT DATABASE()")) {
$row = $result->fetch_row();
$result->close();}
$mysqli->select_db("publications");
if ($result = $mysqli->query("SELECT DATABASE()")) {
$row = $result->fetch_row();
printf("Default database is %s.\n", $row[0]);
$result->close();}
$mysqli->close();
?>
<?php
function getclassics($conn) {
$sql = 'SELECT author FROM classics';
foreach ($conn->query($sql) as $row) {
print $row['author'] . "\t"; }}
?>