@Test
  public void testHasView() throws IllegalPathException {
    ClusterSchemaTree schemaTree = new ClusterSchemaTree();
    schemaTree.appendSingleMeasurement(
        new PartialPath("root.db.db.s1"),
        new MeasurementSchema("s1", TSDataType.INT32),
        null,
        null,
        null,
        false);
    Assert.assertFalse(schemaTree.hasLogicalViewMeasurement());
    schemaTree.appendSingleMeasurement(
        new PartialPath("root.db.view.s1"),
        new LogicalViewSchema("s1", new TimeSeriesViewOperand("root.db.d.s1")),
        null,
        null,
        null,
        false);
    Assert.assertTrue(schemaTree.hasLogicalViewMeasurement());
  }
Generate the following tree: root.sg.d1.s1, root.sg.d1.s2(status) root.sg.d2.s1,
root.sg.d2.s2(status) root.sg.d2.a.s1, root.sg.d2.a.s2(status)
iotdb-core/datanode/src/test/java/org/apache/iotdb/db/queryengine/common/schematree/ClusterSchemaTreeTest.java