LeetCode 627 - Swap Salary

https://leetcode.com/problems/swap-salary/
create table if not exists salary(id int, name varchar(100), sex char(1), salary int)
Truncate table salary
insert into salary (id, name, sex, salary) values ('1', 'A', 'm', '2500')
insert into salary (id, name, sex, salary) values ('2', 'B', 'f', '1500')
insert into salary (id, name, sex, salary) values ('3', 'C', 'm', '5500')
insert into salary (id, name, sex, salary) values ('4', 'D', 'f', '500')

Given a table salary, such as the one below, that has m=male and f=female values. Swap all f and m values (i.e., change all f values to m and vice versa) with a single update statement and no intermediate temp table.

Note that you must write a single update statement, DO NOT write any select statement for this problem.

Example:

| id | name | sex | salary |
|----|------|-----|--------|
| 1  | A    | m   | 2500   |
| 2  | B    | f   | 1500   |
| 3  | C    | m   | 5500   |
| 4  | D    | f   | 500    |

After running your update statement, the above salary table should have the following rows:

| id | name | sex | salary |
|----|------|-----|--------|
| 1  | A    | f   | 2500   |
| 2  | B    | m   | 1500   |
| 3  | C    | f   | 5500   |
| 4  | D    | m   | 500    |

https://leetcode.com/articles/swap-salary/

To dynamically set a value to a column, we can use UPDATE statement together when CASE...WHEN...flow control statement.

https://leetcode.com/problems/swap-salary/discuss/104713/Accept-solution-with-xor

update salary set sex = CHAR(ASCII('f') ^ ASCII('m') ^ ASCII(sex));

https://leetcode.com/problems/swap-salary/discuss/104716/Short-and-Simple

UPDATE salary
    SET sex  = (CASE WHEN sex = 'm' 
        THEN  'f' 
        ELSE 'm' 
        END)