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 (
    92091, 92092, 92093, 92094, 92095, 92096, 
    92097, 83113, 83123, 83990, 83991, 
    83992, 83993, 89614, 89627, 83100, 
    85532, 91294, 84106, 89615, 89628, 
    90071, 84114, 89007, 89009, 83094, 
    83107, 83108, 84113, 91295, 83110, 
    83120, 89008, 90063, 90065, 90076, 
    89739, 89725, 83946, 83947, 83948, 
    83949, 85657, 86388, 84100, 83093, 
    86221, 89727
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00084

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "21.63"
    },
    "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": "16.83",
        "eval_cost": "4.80",
        "prefix_cost": "21.63",
        "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 (92091,92092,92093,92094,92095,92096,92097,83113,83123,83990,83991,83992,83993,89614,89627,83100,85532,91294,84106,89615,89628,90071,84114,89007,89009,83094,83107,83108,84113,91295,83110,83120,89008,90063,90065,90076,89739,89725,83946,83947,83948,83949,85657,86388,84100,83093,86221,89727)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}