## 627. Swap Salary

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 query and no intermediate temp table.

For example:

```| id | name | sex | salary |
|----|------|-----|--------|
| 1  | A    | m   | 2500   |
| 2  | B    | f   | 1500   |
| 3  | C    | m   | 5500   |
| 4  | D    | f   | 500    |
```
After running your query, 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    |
```

b'
\n\n

## Solution

\n
\n

#### Approach: Using `UPDATE` and `CASE...WHEN` [Accepted]

\n

Algorithm

\n

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

\n

MySQL

\n
`UPDATE salary\nSET\n    sex = CASE sex\n        WHEN \'m\' THEN \'f\'\n        ELSE \'m\'\n    END;\n`
\n
'