SELECT 
  cscart_ult_product_prices.product_id, 
  MIN(
    IF(
      cscart_ult_product_prices.percentage_discount = 0, 
      cscart_ult_product_prices.price, 
      cscart_ult_product_prices.price - (
        cscart_ult_product_prices.price * cscart_ult_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_ult_product_prices 
WHERE 
  cscart_ult_product_prices.product_id IN (
    344, 345, 346, 412, 413, 414, 1366, 1367, 
    1368, 1369, 1370, 1371, 1372, 1373, 
    1374, 1375, 1376, 1377, 1378, 1379, 
    1380, 1381, 1382, 1383
  ) 
  AND cscart_ult_product_prices.lower_limit = 1 
  AND cscart_ult_product_prices.company_id = 1 
  AND cscart_ult_product_prices.usergroup_id IN (0, 0, 1) 
GROUP BY 
  cscart_ult_product_prices.product_id

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}