SQL – How to calculate product discount and get products where discount is greater than 25?

I want to calculate discount in SQL query and want to get products having discount greater than 25. I am trying with following query. Please correct me what i am doing wrong. Thank you

SELECT *, (product_price - product_sell_price) / product_sell_price*100 as p_discount
FROM `products`
WHERE product_price IS NOT NULL
  AND p_discont > 25
ORDER BY p_discount DESC

I am getting following error.

#1054 - Unknown column 'p_discont' in 'where clause'

Answer

use inline condition in where clause

SELECT *, (((product_price - product_sell_price) / product_sell_price)*100) as p_discount
FROM `products`
WHERE product_price IS NOT NULL
  AND (((product_price - product_sell_price) / product_sell_price)*100) > 25
ORDER BY p_discount DESC