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 (
    88961, 85800, 82352, 91937, 91939, 91940, 
    91941, 91942, 91943, 88957, 88958, 
    85644, 88942, 86856, 88969, 88970, 
    88973, 88974, 87280, 87288, 85580, 
    86863, 82386, 88094, 89442, 89444, 
    88967, 88968, 88971, 88972, 88955, 
    88956, 92151, 92152, 92153, 92353, 
    92354, 92355, 92356, 88953, 88954, 
    87879, 82403, 82410, 82424, 91893, 
    91894, 91895
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00095

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 (88961,85800,82352,91937,91939,91940,91941,91942,91943,88957,88958,85644,88942,86856,88969,88970,88973,88974,87280,87288,85580,86863,82386,88094,89442,89444,88967,88968,88971,88972,88955,88956,92151,92152,92153,92353,92354,92355,92356,88953,88954,87879,82403,82410,82424,91893,91894,91895)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}