public String getSubscriptionId() {
    final StringBuilder subscriptionId =
        new StringBuilder(topicMeta.getTopicName() + "_" + consumerGroupId);
    getCreationTime().ifPresent(creationTime -> subscriptionId.append("_").append(creationTime));
    return subscriptionId.toString();
  }
SubscriptionMeta is created for show subscription and is not stored in meta keeper.
iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/subscription/meta/subscription/SubscriptionMeta.java