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 (
    415596, 416111, 416112, 416119, 416129, 
    416142, 416146, 416148, 416866, 416874, 
    416878, 416889, 416897, 416902, 416909, 
    416914, 416916, 416920, 417420, 417422, 
    417432, 417443, 418191, 418194
  ) 
  AND product_descriptions.lang_code = 'en'

Query time 0.00586

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "19.99"
    },
    "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": "17.59",
        "eval_cost": "2.40",
        "prefix_cost": "19.99",
        "data_read_per_join": "122K"
      },
      "used_columns": [
        "product_id",
        "lang_code",
        "short_description",
        "full_description"
      ],
      "attached_condition": "((`goimagine`.`product_descriptions`.`product_id` in (415596,416111,416112,416119,416129,416142,416146,416148,416866,416874,416878,416889,416897,416902,416909,416914,416916,416920,417420,417422,417432,417443,418191,418194)) and (`goimagine`.`product_descriptions`.`lang_code` = 'en'))"
    }
  }
}