MySQL packet statistics and list the percentage

SELECT
result,
n,
round( n / s * 100, 5 ) rat 
FROM
(
SELECT
* 
FROM
( SELECT result, count( 1 ) n FROM sendsms_log GROUP BY result ) t1
INNER JOIN ( SELECT count( 1 ) s FROM sendsms_log ) t2 ON 1 = 1 
) t

Wherein "SELECT result, count (1) n FROM sendsms_log GROUP BY result" message transmission result is packet isolated Statistics, "SELECT count (1) s FROM sendsms_log" number of records of all isolated, round (n / s * 100, 5 ) calculating the percentage, to five decimal places. effect:

result	n	rat
Extreme	100	10%
Total generation	100	10%
Ichiyo	300	30%
Distribution	500	50%