Question

I have a database design issue. My project is about products and retailers.

• Product table: product_id, product_name, product_description, category_id, quantity_per_unit

• Retailer table: retailer_id, retailer_name, City

• Retailer's Stock table: retailer_id, product_id, unit_price, availability

The Retailer's Stock table links each product with its seller

And also Category table with category_id,category_name,category_description

Now I want to have different sizes, colour and brands in product. How should I accommodate them in this database? I have included the price in another table then products table because different retailer can sell the same item at different prices.

Answer 1

Your existing database design already meets your stated requirements. Each instance of a combination of size, colour and brand in a product is a row in your Product table. This is often called a Stock Keeping Unit (SKU).

If you want to have products at a higher level, think of breaking your current Product table into two parts, like so:

ProductType ( product_type_id, product_type_name, product_type_description, 
              category_id )

SKU ( sku_id, quantity_per_unit, product_type_id )

Then amend your RetailersStock table to reference SKU instead of Product.