Not sure what to do here.

I notice this is a duplicate question, I'm putting my answer here a second time just in case someone stumbles upon one or the other, but you should consider removing one of them.

$item is an array that contains details about the media item.

$results is a PDOstatement object with our genre results.

Fetch the associative array of $results to loop through, and add an additional "genres" array element to $item. This "genres" element should be an internal associative array with the key of genre_id and the value of genre.

Example $item array:

<?php
array(8) {
    ...
    ["genres"]=>
    array(2) {
        [3]=>
        string(6) "Comedy"
        [16]=>
        string(6) "Sci-Fi"
    }
}

Lets break this down. It tells us that $item is an array that contains details about the media item. To make it more clear, you can test this out yourself and do var_dump($item) and preview, you should see something like this on the screen:

array(7) { ["title"]=> string(50) "Refactoring: Improving the Design of Existing Code" ["category"]=> string(5) "Books" ["img"]=> string(25) "img/media/refactoring.jpg" ["format"]=> string(9) "Hardcover" ["year"]=> string(4) "1999" ["publisher"]=> string(27) "Addison-Wesley Professional" ["isbn"]=> string(14) "978-0201485677" } Alright, so that there is definitely an array about a book, and it tells us exactly what's in the array.

Then it says $results is a PDOstatement object with genre results. What's that mean? Again, check with var_dump:

object(PDOStatement)#3 (1) { ["queryString"]=> string(217) "SELECT * FROM Media JOIN Media_Genres ON Media.media_id = Media_Genres.media_id JOIN Genres ON Media_Genres.genre_id = Genres.genre_id WHERE Media.media_id=?" } and there's our sql query.

From there, it says to loop through the results object. We learned from the previous videos to do that we would use a while loop, like so:

<?php
while($row =  $results->fetch(PDO::FETCH_ASSOC)) {
}

Alright cool, but what data is being processed? Again, var_dump coming in in the clutch:

array(8) { ["media_id"]=> string(1) "3" ["title"]=> string(50) "Refactoring: Improving the Design of Existing Code" ["img"]=> string(25) "img/media/refactoring.jpg" ["genre_id"]=> string(2) "17" ["format"]=> string(9) "Hardcover" ["year"]=> string(4) "1999" ["category"]=> string(5) "Books" ["genre"]=> string(4) "Tech" } array(8) { ["media_id"]=> string(1) "3" ["title"]=> string(50) "Refactoring: Improving the Design of Existing Code" ["img"]=> string(25) "img/media/refactoring.jpg" ["genre_id"]=> string(2) "51" ["format"]=> string(9) "Hardcover" ["year"]=> string(4) "1999" ["category"]=> string(5) "Books" ["genre"]=> string(8) "Business" }

Alright! here's the array we need to add the genre id key and genre value pair to the items array. This is something also learned in the video, but simply put:

<?php
$item[$key] = $value

And for the genre array key to have an associative array as a it's value, you just make the value an array!

<?php
$assocarray[$key] = $value;

So if you put it all together, we should get something like:

<?php
while($row =  $results->fetch(PDO::FETCH_ASSOC)) {
$genreID = $row["genre_id"];
$genre = $row["genre"];
$genreArr[$genreID] = $genre;
$item["genres"] = $genreArr;
}
return $item;

If you're confused about any of this, rewatch the prior video's, they help a lot! (this isn't the only way to do this, so be open to doing it in other better/worse ways!)