SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = '1FBO-9KPZ-9M2T-D5N0-LBPN-E9B3-RT8V-AUUK' 
  AND product_id = 94 
  AND expires_at > 1777993057 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00031

JSON explain

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