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 (
    91905, 91906, 91907, 91908, 91909, 91910, 
    91911, 84268, 89735, 91904, 89435, 
    82417, 86852, 89433, 82399, 86848, 
    84265, 89731, 89431, 83088, 89124, 
    89128, 89160, 89551, 91290, 82332, 
    86814, 86844, 89101, 91286, 90093, 
    90103, 90112, 83115, 83125, 83134, 
    90120, 89199, 83142, 91282, 84121, 
    89202, 83145, 84124, 92841, 94077, 
    94689, 94713, 96714, 96755, 96770, 
    97014, 97019, 97035, 97042, 97048, 
    97054, 97813, 97837, 97991, 98033, 
    98157, 98161, 98165, 98700, 98738, 
    98742, 98746, 99573, 99583, 99587, 
    100070, 100154, 100170, 100172, 100174, 
    100324, 100607, 100885, 100901, 100908, 
    100914, 100920, 101113, 101122, 101131, 
    101515, 101524, 101533, 101553, 101562, 
    101571
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00147

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "41.44"
    },
    "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": 92,
      "rows_produced_per_join": 92,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "32.24",
        "eval_cost": "9.20",
        "prefix_cost": "41.44",
        "data_read_per_join": "350K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (91905,91906,91907,91908,91909,91910,91911,84268,89735,91904,89435,82417,86852,89433,82399,86848,84265,89731,89431,83088,89124,89128,89160,89551,91290,82332,86814,86844,89101,91286,90093,90103,90112,83115,83125,83134,90120,89199,83142,91282,84121,89202,83145,84124,92841,94077,94689,94713,96714,96755,96770,97014,97019,97035,97042,97048,97054,97813,97837,97991,98033,98157,98161,98165,98700,98738,98742,98746,99573,99583,99587,100070,100154,100170,100172,100174,100324,100607,100885,100901,100908,100914,100920,101113,101122,101131,101515,101524,101533,101553,101562,101571)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}