What are the names of products and their corresponding colors?
select t1.product_name, t2.color_description from products as t1 join ref_colors as t2 on t1.color_code = t2.color_code
Filter to show only the ones with "green" color.
select t1.product_name, t2.color_description from products as t1 join ref_colors as t2 on t1.color_code = t2.color_code where t2.color_description = "green"
Show the ones that have "yellow" color instead.
select t1.product_name, t2.color_description from products as t1 join ref_colors as t2 on t1.color_code = t2.color_code where t2.color_description = "yellow"
Instead of showing the color description, show their typical buying and selling prices.
select t1.product_name, t1.typical_buying_price, t1.typical_selling_price from products as t1 join ref_colors as t2 on t1.color_code = t2.color_code where t2.color_description = "yellow"