@Override
  public final void postTearDownCacheTestCase() throws Exception {
    Invoke.invokeInEveryVM(QueryObserverHolder::reset);
    cache = null;
    Invoke.invokeInEveryVM(new SerializableRunnable() {
      @Override
      public void run() {
        cache = null;
      }
    });
  }
This tests the querying using a RegionFunctionContext which provides a filter (routing keys) to
run the query on subset of buckets "locally". If query includes buckets
geode-core/src/distributedTest/java/org/apache/geode/cache/query/dunit/QueryUsingFunctionContextDUnitTest.java