SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a58db9a53ed448e256b4021091bbf746af6aeb57f80e0a83e88e735cba225393' 
  AND token = '9+ZVwIG5J1oGChDLm26XGd04mjyq1rZvoq7yMFUyp1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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