Calculate Contest Registration Percentages with the Source Tie Order

### Problem For each contest present in Register, report contest_id and percentage of all Users registered in it, rounded to two decimal places. Sort percentage descending, then contest_id ascending for equal percentages. ### Tables Table: `Users` ```text +-------------+---------+ | Column Name | Type | +-------------+---------+ | user_id | int | | user_name | varchar | +-------------+---------+ user_id is the primary key (column with unique values) for this table. Each row of this table contains the name and the id of a user. ``` Table: `Register` ```text +-------------+---------+ | Column Name | Type | +-------------+---------+ | contest_id | int | | user_id | int | +-------------+---------+ (contest_id, user_id) is the primary key (combination of columns with unique values) for this table. Each row of this table contains the id of a user and the contest they registered into. ``` ### Constraints - In this version, every `Register.user_id` references an existing `Users.user_id`. ### Example ```text Users (user_id,user_name): (1,Ada), (2,Bo), (3,Cam), (4,Dee) Register (contest_id,user_id): (20,1), (20,2), (10,3), (10,4), (30,1) Output (contest_id,percentage): (10,50.00), (20,50.00), (30,25.00) ``` ### What a Strong Answer Covers - Use all users as the denominator for each registered contest. - Round percentages to the requested precision and apply the stated tie order. ### Follow-up Questions - How would you show contests with zero registrations if a contest table were available? - How would you compare percentages using only users eligible for each contest?