acp_forums::move_forum_content PHP Method

    function move_forum_content($from_id, $to_id, $sync = true)
    {
        global $db, $phpbb_dispatcher;
        $errors = array();
        /**
         * Event when we move content from one forum to another
         *
         * @event core.acp_manage_forums_move_content
         * @var	int		from_id		If of the current parent forum
         * @var	int		to_id		If of the new parent forum
         * @var	bool	sync		Shall we sync the "to"-forum's data
         * @var	array	errors		Array of errors, should be strings and not
         *							language key. If this array is not empty,
         *							The content will not be moved.
         * @since 3.1.0-a1
         */
        $vars = array('from_id', 'to_id', 'sync', 'errors');
        extract($phpbb_dispatcher->trigger_event('core.acp_manage_forums_move_content', compact($vars)));
        // Return if there were errors
        if (!empty($errors)) {
            return $errors;
        }
        $table_ary = array(LOG_TABLE, POSTS_TABLE, TOPICS_TABLE, DRAFTS_TABLE, TOPICS_TRACK_TABLE);
        foreach ($table_ary as $table) {
            $sql = "UPDATE {$table}\n\t\t\t\tSET forum_id = {$to_id}\n\t\t\t\tWHERE forum_id = {$from_id}";
            $db->sql_query($sql);
        }
        unset($table_ary);
        $table_ary = array(FORUMS_ACCESS_TABLE, FORUMS_TRACK_TABLE, FORUMS_WATCH_TABLE, MODERATOR_CACHE_TABLE);
        foreach ($table_ary as $table) {
            $sql = "DELETE FROM {$table}\n\t\t\t\tWHERE forum_id = {$from_id}";
            $db->sql_query($sql);
        }
        if ($sync) {
            // Delete ghost topics that link back to the same forum then resync counters
            sync('topic_moved');
            sync('forum', 'forum_id', $to_id, false, true);
        }
        return array();
    }