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PHP Integrating PHP with Databases Limiting Records in SQL Calculations and Links

Geraldo Hernandez
Geraldo Hernandez
7,515 Points
Posted by Geraldo Hernandez
Geraldo Hernandez
7,515 Points

How does the ampersand (&) allow us to pass the page number?

From the video, when Alena is limiting the results in redirect, she writes the following code:

if(isset($_GET["pg"])){
    $current_page = filter_input(INPUT_GET, "pg", FILTER_SANITIZE_NUMBER_INT);
}
if(empty($current_page)){
    $current_page = 1;
}

$total_items = get_catalog_count($section);

$total_page = ceil($total_items / $items_per_page);     // round upward

// redirect too-large page numbers to the last page
if($current_page > $total_pages){
    header("location:catalog.php?pg="
        . $limit_results
        . "pg=" . $total_pages);
}
// redirect too-small page numbers to the first page
if($current_page < 1){
    header("location:catalog.php?pg=1");
}

// limit results
$limit_results = '';
if(!empty($section)){
    // ampersand (&) at end will allow us to pass page number
    $limit_results = "cat=" . $section . "&";
}

I'm confused as to how she uses the ampersand to grab the current page number. The part in question is at the very last few lines of code.