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 (
    87668, 87667, 87689, 87688, 87651, 87790, 
    87789, 87681, 87758, 87757, 87756, 
    87755, 87684, 87677, 87585, 87885, 
    88049, 88048, 88047, 88046, 88045, 
    87873, 87766, 87765, 87646, 87590, 
    87589, 88131, 88130, 88129, 88128, 
    88071, 88070, 88069, 88057, 88056, 
    88055, 87482, 87481, 87487
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id