/* Remove expired cache entries. */
        q('DELETE FROM {SQL_TABLE_PREFIX}search_cache WHERE expiry<'. (__request_timestamp__ - $GLOBALS['SEARCH_CACHE_EXPIRY']));

        if (!($total = q_singleval('SELECT count(*) FROM {SQL_TABLE_PREFIX}search_cache WHERE srch_query=\''. $qry_lck .'\' AND query_type='. $qt))) {
            if (defined('plugins') && isset($plugin_hooks['UPDATE_SEARCH_CACHE'])) {
                plugin_call_hook('UPDATE_SEARCH_CACHE', array($qry_lck, $tbl, $qt, $wa));
            } else {
                q('INSERT INTO {SQL_TABLE_PREFIX}search_cache (srch_query, query_type, expiry, msg_id, n_match) '.
                  q_limit('SELECT \''. $qry_lck .'\', '. $qt .', '. __request_timestamp__ .', msg_id, count(*) as word_count FROM {SQL_TABLE_PREFIX}search s INNER JOIN {SQL_TABLE_PREFIX}'. $tbl .' i ON i.word_id=s.id WHERE word IN('. $qr .') GROUP BY msg_id ORDER BY word_count DESC',
                          500, 0));
            }
        }