SELECT 
  1 
FROM 
  cscart_ec_print_temp_designs 
WHERE 
  session_id = '4Z0O-8GNM-1WHC-9IMU-B5I4-8Q7J-RTD0-WQ5Q' 
  AND product_id = 192 
  AND expires_at > 1770197143 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00036

JSON explain

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