Core SQL Query Writing | Dataford Interview Questions

TE Connectivity analysts need a quarterly view of customers purchasing AMP connector products. Write a PostgreSQL query that identifies customers meeting both order-count and sales-value thresholds.

Requirements

Join customers, orders, and order_items.
Include only completed orders placed from January 1 through March 31, 2025, with product_family = 'AMP Connector'.
Return each customer’s completed order count and total connector sales, calculated as quantity * unit_price.
Use HAVING to keep customers with at least two qualifying orders and at least $1,000 in sales. Sort by sales descending, then customer name.

Schema

customers

Column	Type	Description
customer_idPK	INT	Customer identifier
customer_name	VARCHAR(100)	Customer name
region	VARCHAR(50)	Sales region

orders

Column	Type	Description
order_idPK	INT	Order identifier
customer_id	INT	Related customer identifier
order_date	DATE	Date the order was placed
order_status	VARCHAR(20)	Order lifecycle status

order_items

Column	Type	Description
order_item_idPK	INT	Line-item identifier
order_id	INT	Related order identifier
product_family	VARCHAR(80)	TE Connectivity product family
product_name	VARCHAR(120)	Product description
quantity	INT	Units ordered
unit_price	DECIMAL(10,2)	Price per unit

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