code: private void writEventToSystemTable(String key, Delta delta, Audit audit) {
          _backingStore.update(_systemTableUnPublishedDatabusEvents, key, TimeUUIDs.newUUID(), delta, audit, WriteConsistency.GLOBAL);
      }
docs: /* Write the delta to the unpublished databus events system table which stores all the drop, purge, attribute changes, placement moves etc information of the tables.