private EffectiveMeta buildEffectiveMeta(final long id, final String effectiveTimeStr) {
        return new EffectiveMeta(id,
                DUMMY_FEED,
                DUMMY_TYPE,
                DateUtil.parseNormalDateTimeString(effectiveTimeStr));
    }
Make sure that it copes with a map not being in an early stream but is in a later one.
stroom-app/src/test/java/stroom/pipeline/refdata/TestReferenceData.java