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 (
    26, 35, 47, 81, 107, 109, 91, 92, 161, 188, 
    202, 203, 34, 31, 38, 80, 165, 166, 86, 
    106, 105, 247, 101, 33, 32, 163, 244, 
    212, 155, 102, 55, 176, 69, 138, 110, 
    36, 206, 28, 184, 183, 133, 132, 125, 
    120, 223, 225, 224, 146, 147, 93, 117, 
    219, 222, 220, 221, 87, 113, 139, 118, 
    83, 157, 123, 174, 171, 280, 282, 278, 
    20, 119, 100, 46, 204, 45, 68, 29, 6, 8, 
    14, 9, 10, 19, 21, 7, 27, 124, 50, 51, 49, 
    48, 54, 44, 194, 137, 153, 164, 236, 234, 
    150, 151, 178, 181, 248, 65, 64, 63, 62, 
    66, 140, 141, 144, 143, 142, 13
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id

Query time 0.00144

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "279.98"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "226.00"
      },
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "ALL",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "rows_examined_per_scan": 254,
        "rows_produced_per_join": 225,
        "filtered": "88.98",
        "cost_info": {
          "read_cost": "8.78",
          "eval_cost": "45.20",
          "prefix_cost": "53.98",
          "data_read_per_join": "5K"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`atulecarter_atul_demo7`.`cscart_product_prices`.`lower_limit` = 1) and (`atulecarter_atul_demo7`.`cscart_product_prices`.`product_id` in (26,35,47,81,107,109,91,92,161,188,202,203,34,31,38,80,165,166,86,106,105,247,101,33,32,163,244,212,155,102,55,176,69,138,110,36,206,28,184,183,133,132,125,120,223,225,224,146,147,93,117,219,222,220,221,87,113,139,118,83,157,123,174,171,280,282,278,20,119,100,46,204,45,68,29,6,8,14,9,10,19,21,7,27,124,50,51,49,48,54,44,194,137,153,164,236,234,150,151,178,181,248,65,64,63,62,66,140,141,144,143,142,13)) and (`atulecarter_atul_demo7`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}