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 (
    430164, 444428, 419787, 428029, 441949, 
    460434, 402472, 433652, 426548, 416330, 
    447518, 427542
  ) 
  AND cscart_product_descriptions.lang_code = 'ar'

Query time 0.00140

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.0216566,
    "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": 12,
          "cost": 0.0216566,
          "filtered": 100,
          "attached_condition": "cscart_product_descriptions.product_id in (430164,444428,419787,428029,441949,460434,402472,433652,426548,416330,447518,427542) and cscart_product_descriptions.lang_code = 'ar'"
        }
      }
    ]
  }
}

Result

product_id short_description full_description unit_name
402472 Lite Router 527 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
416330 Lite Router 877 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
419787 Lite Router 316 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
426548 Lite Router 699 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
427542 Lite Shirt 229 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
428029 Lite Router 331 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
430164 Lite Router 255 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
433652 Lite Router 557 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
441949 Lite Router 362 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
444428 Lite Router 302 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
447518 Lite Shirt 114 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.
460434 Lite Router 448 — high quality, tested and ready to ship. Generated sample data for CS-Cart import.