How do I return a database from within a function to be used in an included file?

Question

I'm running out of options here and I'm not sure what I'm doing wrong. I want to automate the extraction of data from a table and paginate in the process. the code works flawlessly on its own, but as soon as I make it part of a function (to automate the process), it breaks down. I can't seem to be able to "extract" the data from within the function. What I expect is that once I run the function, I can access the results using the $result var, but this doesn't work. What am I doing wrong? The page where I'm trying to render the output is included in the page where I run the function.

function generateDataTable(string $table) {
    global $PDO;

    if(isset($_GET['page']) && !empty($_GET['page']) && ctype_digit($_GET['page'])) { $pageNumber = $_GET['page']; } else { $pageNumber = dataPageNumber; }
    if(isset($_GET['list']) && !empty($_GET['list']) && ctype_digit($_GET['list'])) { $listnumber = $_GET['list']; } else { $listNumber = dataListNumber; }

    if(!empty($_GET['sortby']) && ctype_alnum($_GET['sortby'])) { $sortBy = $_GET['sortby']; } else { $sortBy = 'id'; }
    if(!empty($_GET['sortorder']) && ctype_alnum($_GET['sortorder'])) { $sortOrder = $_GET['sortorder']; } else { $sortOrder = 'ASC'; }

    $rowsCount = getRowsCount($table);
    $lastPage = ceil($rowsCount/$listNumber);

    if ($pageNumber > $lastPage) { $pageNumber = $lastPage; }
    if ($pageNumber < 1) { $pageNumber = 1; }

    $rowsLimitLow = ($pageNumber - 1) * $listNumber;
    $rowsLimitHigh = $listNumber;

    $query = $PDO->prepare("SELECT * FROM $table ORDER BY $sortBy $sortOrder LIMIT $rowsLimitLow, $rowsLimitHigh");
    $query->execute();
    $result = $query->fetchAll();

    return $result;
}

this is the page where I run the function and I include a view page (a template) where I'm trying to access the results.

generateDataTable('carrier');

include(DIR_ROOT.'/views/data/default.php');

this is how I'm trying to access the results:

<?php
                foreach($result as $item) {
                    echo '<tr>
                        <td><input type="checkbox" value="'.$carrier['id'].'"></td>
                        <td class="expand"><a href="index.php?module=data&action=view&carrier='.$item['id'].'">'.$item['name'].'</a></td>
                        <td>'.$item['iata_code'].'</td>
                        <td>'.$item['icao_code'].'</td>
                        <td>'.$item['country'].'</td>
                    </tr>';
                }
            ?>

I know that it has to do with the scope of my variables, but I tried everything and it still doesn't work. the other similar questions had some answers, but different situations. I tried declaring $results[] and creating an array with all columns like this:

$results[] = array($result['id'], $result['name'] etc)

but this failed too. Any thoughts?

Answer 1

You need to assign the return value of the function to the variable:

$result = generateDataTable('carrier');