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 (
    92362, 92363, 92364, 85560, 85566, 85641, 
    89988, 91848, 91888, 85569, 91876, 
    85545, 92357, 84237, 85548, 92913, 
    92914, 92915, 92916, 92917, 92918, 
    92919, 92920, 92921, 93283, 93285, 
    93287, 93289, 93291, 93753, 93754, 
    93755, 93756, 93757, 93758, 93759, 
    93760, 93761, 93762, 93763, 93764, 
    93765, 93766, 93767, 93768, 93769, 
    93770, 93771
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00091

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 (92362,92363,92364,85560,85566,85641,89988,91848,91888,85569,91876,85545,92357,84237,85548,92913,92914,92915,92916,92917,92918,92919,92920,92921,93283,93285,93287,93289,93291,93753,93754,93755,93756,93757,93758,93759,93760,93761,93762,93763,93764,93765,93766,93767,93768,93769,93770,93771)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}