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 (
    92401, 92402, 92403, 92404, 92405, 92406, 
    92407, 92400, 92417, 92418, 92419, 
    92420, 92421, 92422, 92416, 92409, 
    92410, 92411, 92412, 92413, 92414, 
    92415, 85599, 85596, 85598, 85590, 
    85595, 85586, 85581, 92408, 87385, 
    82328, 88864, 90819, 90820, 90821, 
    90822, 90817, 90818
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.57"
    },
    "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": 39,
      "rows_produced_per_join": 39,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "13.67",
        "eval_cost": "3.90",
        "prefix_cost": "17.57",
        "data_read_per_join": "148K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`nuie_scalesta_net`.`cscart_product_descriptions`.`product_id` in (92401,92402,92403,92404,92405,92406,92407,92400,92417,92418,92419,92420,92421,92422,92416,92409,92410,92411,92412,92413,92414,92415,85599,85596,85598,85590,85595,85586,85581,92408,87385,82328,88864,90819,90820,90821,90822,90817,90818)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}