A log topic is used to classify logs in a Logstore. You can specify a topic for logs written to Log Service. Then, you can specify the topic when you query the logs. For example, you can use your user ID as the log topic when writing logs. In this way, you can view only your own logs based on the log topic when querying logs. If you do not need to classify logs in a Logstore, use the same topic for all logs.

Note The default log topic for log data writes and queries is an empty string. If you do not specify a log topic, you can use the empty string as the default topic to write or query logs.

The relationships among Logstores, log topics, and logs are described as follows: