Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '51a5e32b4bb8b76a5a43c5da4e1225d5e0d09b9ab693b87e14ee34f36b4aa965' 
  AND token = 'WkRIFJ7m6UwfkOM19H+RJl6DK0Tk/YC0vYM5JZiaqQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}