Hello @pzsnz ,
First, I just want to make sure I am understanding you correctly. You are looking to copy a measurement into a new DB with the same tags but ommit just one tag?
So Telegraf is a collection agent. It’s the tool you can use to collect data and send it to the DB of your choosing. Alternatively you can also use a Client Library or http endpoint to interact with the database (to write or query).
Kapacitor is a real-time stream processing engine and alert manager. Once you collect your data with telegraf, you can send it to kapacitor first if you want. Kapacitor can transform your data ( for example a simple transformation would be to average your data) before you store it in influxdb. Or you can send your data to influxdb first, and then use kapacitor to apply transformations to your data after. It’s up to you! You can also manage alerts with kapacitor. For example, if your data exceeds a certain threshold, you can use kapacitor to register that threshold crossing and send an alert to slack, email, txt etc.
As you start learning about Kapacitor you will eventually come across Continuous Queries. Please read this to learn about the difference:
While I wait for your response, I wanted to share some learning resource to help you out.
Intro to InfluxData