Calculation of percentage of group count(*)

Question

Select * from Namelist;
Name      Age
Sathish   25
Sathish   65
Sathish   55
Sathish   45
Sathish   35
Jana      55
Jana      25
Jana      10
Bala      55
Bala      26

How to get Percentage value for given format;

Name   Count   Percentege
Sathish  5     50%
Jana     3     30%
Bala     2     20%

Kindly share sql query?

Answer 1

This is a slightly sexier version of some of the other answers - note the use of sum(100) to avoid the longer (and more mundane) count(*) * 100 :)

select name, count(*) as count, sum(100) / total as percentage
from namelist
cross join (select count(*) as total from namelist) x
group by 1

Answer 2

This query(not tested) should work :

SELECT Name,
COUNT(*) AS Count,
(COUNT(*) / _total ) * 100 AS Percentege
FROM Namelist,
(SELECT COUNT(*) AS _total
  FROM Namelist) AS myTotal
GROUP BY Name;