@Override
        public LmdbKV makeUnique(final LmdbKV lmdbKV) {
            // If this isn't a group key then make it unique.
            if (isDetailLevel(getDepth(lmdbKV))) {
                lmdbKV.key().putLong(lmdbKV.key().limit() - Long.BYTES,
                        uniqueIdProvider.getUniqueId());
            }
            return lmdbKV;
        }
Creates a nested time based group key. <DEPTH><TIME_MS><PARENT_GROUP_HASH><GROUP_HASH>
stroom-query/stroom-query-common/src/main/java/stroom/query/common/v2/LmdbRowKeyFactoryFactory.java