SELECT 
  cscart_product_descriptions.product_id, 
  cscart_product_descriptions.short_description, 
  IF(
    cscart_product_descriptions.short_description = '' 
    OR cscart_product_descriptions.short_description IS NULL, 
    cscart_product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    94160, 94381, 94428, 94452, 94453, 94454, 
    94455, 94456, 94457, 94458, 94459, 
    94460, 94461, 94462, 94558, 94559, 
    94560, 94561, 94562, 94563, 94564, 
    94565, 94566, 94567, 94568, 94569, 
    94570, 94571, 94572, 94583, 94584, 
    94585, 94586, 94587, 94588, 94604, 
    94605, 94606, 94607, 94608, 94609, 
    94610, 94611, 94612, 94613, 94614, 
    94615, 94616
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00054

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "21.62"
    },
    "table": {
      "table_name": "cscart_product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "9",
      "rows_examined_per_scan": 48,
      "rows_produced_per_join": 48,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "16.82",
        "eval_cost": "4.80",
        "prefix_cost": "21.62",
        "data_read_per_join": "183K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (94160,94381,94428,94452,94453,94454,94455,94456,94457,94458,94459,94460,94461,94462,94558,94559,94560,94561,94562,94563,94564,94565,94566,94567,94568,94569,94570,94571,94572,94583,94584,94585,94586,94587,94588,94604,94605,94606,94607,94608,94609,94610,94611,94612,94613,94614,94615,94616)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}