How to Divide one Column by Another in MySQL or Oracle

Problem:

You want to divide one column by another in MySQL or Oracle.

Example:

An online store has an orders table with data in the columns order_id, total_order_payment, and item_count.

Let’s say we want to extract the average cost per item for each order, i.e., the total payment for the order divided by the item count.

Solution:

A query to do this is:

SELECT
  order_id,
  total_order_payment / item_count AS average_item_cost
FROM orders;

Here’s what you get with this query:

Discussion:

To divide a column by another in MySQL and Oracle, use the division operator /. Put the first column or expression before the / operator and the second column or expression after the / operator.

You may use the division operator / to divide by constant values as well. For example, to find out the price with a 50% discount, use this query:

SELECT 
  order_id, 
  total_order_payment / 2 AS payment_after_discount
FROM orders;