Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b256c1552ba7b399010806583834f012240a78ee7ff25a338fe4da6a98a14dca' 
  AND token = 'oGaLb+aRcBQP599S/XQQnNIKKDlXzEa8p/3NZ+sFtKM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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