Category Revenue Leaders

SQL practice question · Medium · Window Functions · Amazon

fulfillment_orders has one row per sale (category, item, revenue); the same item can appear on several rows. First total the revenue of each item within its category, then return the highest-grossing item of each category; if several items tie for the top total, return all of them. Output columns: category, item, revenue (the item's total, rounded to 2 decimals). Order by category, then item.

Table: fulfillment_orders

Schema of fulfillment_orders
Column	Type
category	TEXT
item	TEXT
revenue	REAL

Schema of fulfillment_orders

Column

Type

Sample rows of fulfillment_orders
category	item	revenue
Electronics	Phone	500
Electronics	Tablet	300
Home	Chair	250
Home	Lamp	250
Home	Desk	400

Expected output on the sample data
category	item	revenue
Electronics	Phone	500
Home	Desk	400

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