Hi,

1) You should set the page to PHP (menu Page->Extension or Server scripts in older versions)

2) You can add a Code Block Source type PHP (or any other type in which case you should insert <?php .. ?> tags yourself

3) Connect to DB and read data into a variable, e.g. $rows.

4) Now depending on how you handle your tables, you can either transform this into a Javascript variable or generate the table directly by PHP. Example of the latter: add a Code Block Visual where you need your table to be, inside which:

<table class='my-table-class'>
<?php
foreach($rows as $row) {
  echo "<tr><td>{$row['name']}</td><td>{$row['address']}</td></tr>";
}
?>
</table>