MySQL Calculate Percentage

Question

I have a MySQL database with 4 items: id (numerical), group_name, employees, and surveys.

In my SELECT

Answer 1

try this

   SELECT group_name, employees, surveys, COUNT( surveys ) AS test1, 
        concat(round(( surveys/employees * 100 ),2),'%') AS percentage
    FROM a_test
    GROUP BY employees

DEMO HERE