@Test
  public void testQueryWithNULLInWhereClause() throws Exception {
    final Host host = Host.getHost(0);
    VM server = host.getVM(0);
    VM client = host.getVM(1);
    VM producer = host.getVM(2);

    createServer(server);

    final int thePort = server.invoke(CqQueryUsingPoolDUnitTest::getCacheServerPort);
    final String host0 = NetworkUtils.getServerHostName(server.getHost());

    String poolName = "testQueryWithNULLInWhereClause";
    createPool(client, poolName, host0, thePort);

    // Create client.
    // createClient(client, thePort, host0);

    // producer is not doing any thing.
    createClient(producer, thePort, host0);

    final int size = 50;
    createValues(producer, regions[0], size);

    createCQ(client, poolName, "testQuery_9", cqs[9]);
    executeCQ(client, "testQuery_9", true, null);

    createValues(producer, regions[0], (2 * size));

    for (int i = 1; i <= size; i++) {
      if (i % 2 == 0) {
        waitForUpdated(client, "testQuery_9", KEY + i);
      }
    }

    for (int i = (size + 1); i <= 2 * size; i++) {
      if (i % 2 == 0) {
        waitForCreated(client, "testQuery_9", KEY + i);
      }
    }

    validateCQ(client, "testQuery_9", noTest, 25, 25, noTest);

    // Close.
    closeClient(client);
    closeServer(server);
  }
Tests execution of queries with NULL in where clause like where ID = NULL etc.
geode-cq/src/distributedTest/java/org/apache/geode/cache/query/cq/dunit/CqQueryUsingPoolDUnitTest.java