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 (
    83335, 83345, 83048, 90884, 90963, 82827, 
    82828, 82900, 82901, 82973, 82974, 
    83235, 82849, 82922, 82995, 83479, 
    83487, 86626, 86695, 85313, 85410, 
    85461, 85512, 82596, 83359, 83272, 
    85359, 83557, 86499, 86775, 86634, 
    86703, 83155, 83160, 82818, 82891, 
    82964, 83338, 83348, 82826, 82899, 
    82972, 82608, 82609, 82630, 83495, 
    82599, 83362
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00131

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 (83335,83345,83048,90884,90963,82827,82828,82900,82901,82973,82974,83235,82849,82922,82995,83479,83487,86626,86695,85313,85410,85461,85512,82596,83359,83272,85359,83557,86499,86775,86634,86703,83155,83160,82818,82891,82964,83338,83348,82826,82899,82972,82608,82609,82630,83495,82599,83362)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}