@Override
      public void run2() throws CacheException {
        Region region1 = getRootRegion().getSubregion(regions[0]);
        for (int i = -1; i >= -5; i--) {
          region1.put(KEY + i, KEY + i);
        }
      }
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/CqQueryDUnitTest.java