SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = '5A4E-DQ5D-05H1-N6WB-Y2JW-4IJ0-S5OX-17KE' 
  AND product_id = 140 
  AND expires_at > 1777170527 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00029

JSON explain

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