@Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (!(o instanceof MinLabeledFunction)) {
            return false;
        }
        MinLabeledFunction function = (MinLabeledFunction) o;
        return Objects.equals(entityId, function.entityId) &&
                getTimeBucket() == function.getTimeBucket();
    }
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