Write a SQL query to find the top three highest-performing product categories by sales volume from an e-commerce database.
For this exercise, sales volume means the total quantity of units sold across order items.
category_name and total_units_sold.total_units_sold descending, then category_name ascending to break ties.| Column | Type | Description |
|---|---|---|
| category_idPK | INT | Unique product category identifier |
| category_name | VARCHAR(100) | Product category name |
| Column | Type | Description |
|---|---|---|
| product_idPK | INT | Unique product identifier |
| product_name | VARCHAR(150) | Product name |
| category_id | INT | Category associated with the product |
| Column | Type | Description |
|---|---|---|
| order_item_idPK | INT | Unique order item identifier |
| product_id | INT | Product included in the order item |
| quantity | INT | Number of units sold |