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, 
  cscart_product_descriptions.unit_name 
FROM 
  cscart_product_descriptions 
WHERE 
  cscart_product_descriptions.product_id IN (
    442715, 430741, 406089, 410471, 409489, 
    412459, 424229, 448141, 452096, 435935, 
    450361, 410461, 454777, 444113, 417555, 
    428819, 454049, 459252, 405167, 401806, 
    425534, 458860, 447690, 422606
  ) 
  AND cscart_product_descriptions.lang_code = 'en'

Query time 0.00091

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.04252208,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_descriptions",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "product_id"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["product_id", "lang_code"],
          "loops": 1,
          "rows": 24,
          "cost": 0.04252208,
          "filtered": 100,
          "attached_condition": "cscart_product_descriptions.product_id in (442715,430741,406089,410471,409489,412459,424229,448141,452096,435935,450361,410461,454777,444113,417555,428819,454049,459252,405167,401806,425534,458860,447690,422606) and cscart_product_descriptions.lang_code = 'en'"
        }
      }
    ]
  }
}

Result

product_id short_description full_description unit_name
401806 Prime Shirt 347 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
405167 Prime Shirt 337 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
406089 Prime Mixer 235 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
409489 Prime Mixer 374 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
410461 Prime Phone 857 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
410471 Prime Mixer 317 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
412459 Prime Mixer 544 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
417555 Prime Router 204 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
422606 Prime Shirt 586 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
424229 Prime Phone 223 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
425534 Prime Shirt 357 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
428819 Prime Router 886 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
430741 Prime Mixer 154 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
435935 Prime Phone 434 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
442715 Prime Laptop 978 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
444113 Prime Router 164 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
447690 Prime Shirt 499 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
448141 Prime Phone 234 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
450361 Prime Phone 519 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
452096 Prime Phone 250 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
454049 Prime Shirt 202 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
454777 Prime Phone 925 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
458860 Prime Shirt 454 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
459252 Prime Shirt 303 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.