Of the total number of players of my game, what percentage of them are paying users?

You want to know what percent of your players are paying players.

select  concat(string( 100*( paying_users/total_users)),'%')   as  paying_percentage , paying_users     from 
(select  COUNT(distinct customer_user_id) AS  total_users,
              sum( is_paying ) as paying_users from accounts   ) 
Segentation
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