SELECT 
  1 
FROM 
  cscart_ec_print_temp_designs 
WHERE 
  session_id = '3FK5-PLGW-N6J7-DRQQ-E0KA-HIMB-OD53-NA2N' 
  AND product_id = 229 
  AND expires_at > 1770202676 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00048

JSON explain

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