Product Sales Analysis I

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Medium

Description

You have two tables: Sales and Product. Each row in Sales records a sale of a product in a given year at a given price. Write a SQL query to report the product_name, year, and price for each sale. Return the result in any order.

Database Schema

Sales

Column Name	Type	Description
sale_id	INT	Part of primary key
product_id	INT	FK to Product
year	INT	Year of sale (part of primary key)
quantity	INT	Quantity sold
price	INT	Price per unit

Product

Column Name	Type	Description
product_id	INT	Primary key
product_name	VARCHAR	Name of product

Example

Sales

sale_id	product_id	year	quantity	price
1	100	2008	10	5000
2	100	2009	12	5000
7	200	2011	15	9000

Product

product_id	product_name
100	Nokia
200	Apple
300	Samsung

Output

product_name	year	price
Nokia	2008	5000
Nokia	2009	5000
Apple	2011	9000

Explanation:

Nokia (product_id=100) was sold in 2008 and 2009 for 5000. Apple (product_id=200) was sold in 2011 for 9000. Samsung has no sales.

Approach hint

Start with a simple approach, explain the trade-off, then move toward a cleaner or more scalable solution.

Common mistake

Skipping assumptions, edge cases, or trade-offs can make an otherwise good answer feel incomplete.