<?php

$id_user = $_SESSION[id_user];

$youtubeQuery = mysqli_query($conn, "INSERT INTO youtubePosts (id_user, title, description, link) VALUES ({$id_user}, '$ytTitle', '$ytDescription', '$description')");

// make some comment here
$youtubePostQuery = mysqli_query($conn, "SELECT * FROM post WHERE id_user={$id_user} AND description='$description'");

// make some comment here
$ytPostRetrieve = mysqli_fetch_assoc($ytPostRetrieve);

// make some comment here
$ytid_post = $youtubePostRetrieve['id_user'];

// make some comment here
$youtube2Query = mysqli_query($conn, "UPDATE youtubePosts SET id_post='$ytid_post' WHERE id_user={$id_user} AND link='$description'");