When set to true:
It will be automatically populated with the date and time that the data is inserted into the table. It is not the exact date and time the message was received by the MQTT Broker, but it should be very close.
When MQTT persistence has timestamp set, instead of populating the timestamp from the current time, it is populated using the automatic timestamp feature. In this way, the "ts" field is now populated with the current Greenwich Mean Time (GMT).
The timezone is not stored using the timezone of the computer. It is stored as Universal Coordinated Time (UTC), which is also known as Greenwich Mean Time (GMT). It has a timezone offset of zero. This makes it easier for you to convert the timestamp to any time zone you prefer.
"AlterPersistenceTopic" can add this automatic timestamp field later.