@Override
    public Metrics toDay() {
        MinLabeledFunction metrics = (MinLabeledFunction) createNew();
        metrics.setEntityId(getEntityId());
        metrics.setTimeBucket(toTimeBucketInDay());
        metrics.setServiceId(getServiceId());
        metrics.getValue().copyFrom(getValue());
        return metrics;
    }
Service ID is required for sort query.
oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/meter/function/min/MinLabeledFunction.java