SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = 'Q88L-3L7Q-IZ5K-L4UG-AB7R-EU40-0OQ2-6B9H' 
  AND product_id = 224 
  AND expires_at > 1777640644 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}