addDropTableSql('surfbar_urls');
addCreateTableSql('surfbar_urls', "
`url_id` BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
-`url_userid` BIGINT(20) UNSIGNED NOT NULL DEFAULT 0,
+`url_userid` BIGINT(20) UNSIGNED NULL DEFAULT NULL,
`url` VARCHAR(255) NOT NULL DEFAULT '',
`url_last_salt` VARCHAR(255) NOT NULL DEFAULT '',
`url_views_total` BIGINT(20) UNSIGNED NOT NULL DEFAULT 0,