Hello,

I’m currently preparing for a SQL interview and stumbled upon go-to resources and found an interesting problem related to geometry. The problem involves calculating the circumference of a circle using SQL. I found it on the SQL interview questions page here.

**Problem Statement:**

To calculate the circumference of a circle, you need to multiply the diameter of the circle by the mathematical constant π (pi). Implement a SQL query to calculate the circumference of circles stored in a database table named `circles`

. The table has two columns: `id`

and `diameter`

.

Write an SQL query that calculates the circumference for each circle in the `circles`

table and displays the result along with the `id`

of the circle.

**Sample Input:**

I’ve been trying different approaches, but I’m having trouble getting the correct results. Can anyone guide me on how to write the SQL query for this problem? Any help would be greatly appreciated!