Items in foreach loop are somehow not unique - php

Question

I'm inserting some values from a json decoded response to my database, but some of the values somehow get inserted not only in their own rows, but also in other rows that had some of those values. So for example if a row had its own audio, it retains its audio, but it also gets fed with some other rows' video/photo/graffiti. However, those posts that didn't have attachments, retain those fields empty. It's a very weird behavior, and I'm already lost in those loops.
foreach ( $response->posts as $key => $element ) {
$comment_id = $element->id;
$user_id = $element->from_id;
$usersget = $var_hidden_from_this_example;
$user_name = $var_hidden_from_this_example_2;
$user_photo = $var_hidden_from_this_example_3;
$comment_text = $response->posts[$key]->text;
$comment_date = date('Y-m-d H:i:s', $response->posts[$key]->date);
if ( !isset ($element->attachments) ) {
$photo = $graffiti = $video = $audio = null;
}
else {
foreach ( $element->attachments as $key_att => $attachment ) {
if ( $attachment->type == 'photo' ) {
if ( $attachment->photo->album_id == $example_only ) {
$graffitis = array();
$graffitis[] = $attachment->photo->$example_var;
}
else {
$photos = array();
$photos[] = $attachment->photo->$example_var;
}
}
if ( $attachment->type == 'video' ) {
$videos = array();
$videos[] = $example_var2;
}
if ( $attachment->type == 'audio' ) {
$audios = array();
$audios[] = $example_var3;
}
}
if ( isset ($photos) ) {
$photo = implode('\n', $photos);
}
if ( isset ($graffitis) ) {
$graffiti = implode('\n', $graffitis);
}
if ( isset ($videos) ) {
$video = implode('\n', $videos);
}
if ( isset ($audios) ) {
$audio = implode('\n', $audios);
}
}
$data = [
'comment_id' => $comment_id,
'user_id' => $user_id,
'user_name' => $user_name,
'user_photo' => $user_photo,
'url' => $referer,
'comment_text' => $comment_text,
'comment_date' => $comment_date,
'photo' => $photo,
'graffiti' => $graffiti,
'video' => $video,
'audio' => $audio,
];
$sql = "INSERT INTO level_1 (comment_id, user_id, user_name, user_photo, url, comment_text, comment_date, photo, graffiti, video, audio) VALUES (:comment_id, :user_id, :user_name, :user_photo, :url, :comment_text, :comment_date, :photo, :graffiti, :video, :audio)";
$pdo->prepare($sql)->execute($data);
}
In other words, the values photo, graffiti, video, and audio get inserted not only in the respective rows, but the same values get inserted in all table rows that didn't have their own values of such kind (except rows that didn't have any of those - they remain empty as expected).

Answer 1

As was pointed out in the comments, you are not re-initialising your $graffitis arrays etc. unless you see an attachment of that type. So for an element that has no videos, it gets the videos from the previous element that had videos. Try rewriting your loop like this:
$graffitis = $photos = $videos = $audios = array();
foreach ( $element->attachments as $key_att => $attachment ) {
if ( $attachment->type == 'photo' ) {
if ( $attachment->photo->album_id == $example_only ) {
$graffitis[] = $attachment->photo->$example_var;
}
else {
$photos[] = $attachment->photo->$example_var;
}
}
if ( $attachment->type == 'video' ) {
$videos[] = $example_var2;
}
if ( $attachment->type == 'audio' ) {
$audios[] = $example_var3;
}
}