SELECT 
  1 
FROM 
  cscart_ec_print_temp_designs 
WHERE 
  session_id = '79S4-I2WE-HKFA-K9YS-1KLH-II6P-QV3F-N6QY' 
  AND product_id = 67 
  AND expires_at > 1770385873 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00079

JSON explain

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