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 (
    405548, 405558, 405564, 405567, 405572, 
    405576, 405588, 405592, 406355, 406859, 
    406863, 406865, 406866, 406870, 406875, 
    406886, 406912, 407621, 407622, 407642, 
    407645, 407649, 407676, 407679
  ) 
  AND product_descriptions.lang_code = 'en'

Query time 0.00214

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "19.98"
    },
    "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": "17.58",
        "eval_cost": "2.40",
        "prefix_cost": "19.98",
        "data_read_per_join": "122K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`goimagine`.`product_descriptions`.`product_id` in (405548,405558,405564,405567,405572,405576,405588,405592,406355,406859,406863,406865,406866,406870,406875,406886,406912,407621,407622,407642,407645,407649,407676,407679)) and (`goimagine`.`product_descriptions`.`lang_code` = 'en'))"
    }
  }
}