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 (
    92595, 92596, 94707, 94708, 96739, 96985, 
    96986, 96987, 96988, 96989, 96990, 
    96991, 96992, 96993, 96994, 96995, 
    96996, 96997, 96999, 97000, 97001, 
    97002, 97003, 97004, 97005, 97006, 
    97007, 97008, 97009, 97010, 97831, 
    97832, 98290, 98291, 98292, 98293, 
    98294, 98295, 98296, 98297, 98298, 
    98299, 98300, 98301, 98302, 98303, 
    98304, 98305
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00078

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 (92595,92596,94707,94708,96739,96985,96986,96987,96988,96989,96990,96991,96992,96993,96994,96995,96996,96997,96999,97000,97001,97002,97003,97004,97005,97006,97007,97008,97009,97010,97831,97832,98290,98291,98292,98293,98294,98295,98296,98297,98298,98299,98300,98301,98302,98303,98304,98305)) and (`nuie_scalesta_net`.`cscart_product_descriptions`.`lang_code` = 'en'))"
    }
  }
}