@Override
  public long calculateRetainedSizeAfterCallingNext() {
    return deviceOperator.calculateRetainedSizeAfterCallingNext();
  }
The {@link SingleDeviceViewOperator} plays a similar role with {@link DeviceViewOperator} of
adding a device column to current resultSet.

<p>Different from {@link DeviceViewOperator} which merge the resultSet from different devices,
{@link SingleDeviceViewOperator} only focuses on one single device, the goal of it is to add a
device view. It's just a transition and won't change the way data flows.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/process/SingleDeviceViewOperator.java