public function getTagTitlesByPostId($postId)
    {
        // Grab the tag ID's from the post_tag table
        $post_tags = DB::table('post_tag')
            ->where('post_id', '=', $postId)
            ->get()
        ;

        // if there are no tags associated with this post, then return emptiness
        if (empty($post_tags)) {
            return $post_tags;
        }


        // ah, there are tags associated with the post

        // initialize the array that will be returned
        $tagTitles = [];

        // go through each tag_id and grab the tag's title
        foreach ($post_tags as $post_tag) {

            $tag = DB::table('tags')
                ->select('title')
                ->where('id', '=', $post_tag->tag_id)
                ->first();

            $tagTitles[] = $tag->title;
        }

        return $tagTitles;
    }