SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = 'N56V-A0HK-TQR7-J43X-BLM3-2NWV-KB6B-9X6M' 
  AND product_id = 1 
  AND expires_at > 1777136896 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00042

JSON explain

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