Practical SQL Query Writing | Dataford Interview Questions

Tell me about your experience writing SQL queries for practical data tasks. Use the provided relational tables to demonstrate a query that summarizes customers with at least two completed orders during 2025.

Output

One row per qualifying customer with customer_id, customer_name, completed_order_count, total_spend, avg_order_value, latest_order_date, and spend_tier.
Include only customers with at least two completed orders in 2025. Classify spend as High for totals of at least 500, Medium for totals from 250 through 499.99, and Low otherwise.
Order by total_spend descending, then customer_id ascending.

Schema

customers

Column	Type	Description
customer_idPK	INT	Unique customer identifier
customer_name	VARCHAR(100)	Customer display name

orders

Column	Type	Description
order_idPK	INT	Unique order identifier
customer_id	INT	Customer associated with the order
order_date	DATE	Date the order was placed
status	VARCHAR(20)	Order processing status

order_items

Column	Type	Description
order_item_idPK	INT	Unique order item identifier
order_id	INT	Order containing the item
quantity	INT	Number of units purchased
unit_price	DECIMAL(10,2)	Price per unit

Your question is Practical SQL Query Writing. Start with the requirements and the three tables 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