SELECT 
  product_descriptions.product_id, 
  product_descriptions.short_description, 
  IF(
    product_descriptions.short_description = '' 
    OR product_descriptions.short_description IS NULL, 
    product_descriptions.full_description, 
    ''
  ) AS full_description 
FROM 
  product_descriptions 
WHERE 
  product_descriptions.product_id IN (
    470272, 470273, 470284, 470991, 470993, 
    471010, 471014, 471037, 471041, 471582, 
    471588, 472325, 472332, 472333, 472341, 
    472349, 472360, 472361, 472867, 472876, 
    472882, 472883, 472890, 472891
  ) 
  AND product_descriptions.lang_code = 'en'

Query time 0.00152

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "20.14"
    },
    "table": {
      "table_name": "product_descriptions",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "product_id"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "product_id",
        "lang_code"
      ],
      "key_length": "11",
      "rows_examined_per_scan": 24,
      "rows_produced_per_join": 24,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "17.75",
        "eval_cost": "2.40",
        "prefix_cost": "20.15",
        "data_read_per_join": "122K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`goimagine`.`product_descriptions`.`product_id` in (470272,470273,470284,470991,470993,471010,471014,471037,471041,471582,471588,472325,472332,472333,472341,472349,472360,472361,472867,472876,472882,472883,472890,472891)) and (`goimagine`.`product_descriptions`.`lang_code` = 'en'))"
    }
  }
}