@Override
  public List<PlanNode> getChildren() {
    return Collections.emptyList();
  }
{@link PipeOperateSchemaQueueNode} is for pipe to open or close the {@link
SchemaRegionListeningQueue}. It is for written to {@link SchemaRegion} consensus layer to ensure
the identity of the {@link SchemaRegionListeningQueue} in all peers.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/planner/plan/node/pipe/PipeOperateSchemaQueueNode.java