Customers Ordering Last 30 Days | Dataford Interview Questions

Capgemini Invent wants a recent-customer view for monitoring activity in its digital commerce services. Write a PostgreSQL query that identifies customers who placed at least one order during the last 30 days.

Assume CURRENT_DATE is 2026-08-29 when evaluating the sample output.

Requirements

Return each qualifying customer only once, even if the customer placed multiple orders.
Include orders from the current date and the date exactly 30 days before the current date, but exclude future orders.
Sort the results by customer_id in ascending order.

Schema

orders

Column	Type	Description
order_idPK	INTEGER	Unique order identifier
customer_id	INTEGER	Customer identifier
customer_name	VARCHAR(100)	Customer display name
order_date	DATE	Date when the order was placed
sales_channel	VARCHAR(30)	Channel used for the order

Your question is Customers Ordering Last 30 Days. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Assume CURRENT_DATE is 2026-08-29 when evaluating the sample output.

Requirements

Return each qualifying customer only once, even if the customer placed multiple orders.
Include orders from the current date and the date exactly 30 days before the current date, but exclude future orders.
Sort the results by customer_id in ascending order.

Schema

orders

Column	Type	Description
order_idPK	INTEGER	Unique order identifier
customer_id	INTEGER	Customer identifier
customer_name	VARCHAR(100)	Customer display name
order_date	DATE	Date when the order was placed
sales_channel	VARCHAR(30)	Channel used for the order

Your question is Customers Ordering Last 30 Days. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.