SELECT 
  cscart_product_prices.product_id, 
  MIN(
    IF(
      cscart_product_prices.percentage_discount = 0, 
      cscart_product_prices.price, 
      cscart_product_prices.price - (
        cscart_product_prices.price * cscart_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_product_prices 
WHERE 
  cscart_product_prices.product_id IN (
    50219, 50218, 50217, 50216, 50215, 50214, 
    50213, 50212, 50211, 50210, 50209, 
    50208, 50207, 50206, 50205, 50204, 
    50203, 50202, 50201, 50200, 50199, 
    50198, 50197, 50196, 50195
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id