Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a21c852845d887fd7d90674a8cd7e855c505ab02f3e41eee89e24b5ed9d6c1ae' 
  AND token = 'DbTxnqERNbhmiQzfHE6nMLqzYqXxQpguoReFugUa7qU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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