Convert Field into Tags in the same measurement

I have Bcm_Modes field in my measurement it has values 0,1,2,3 i wanted to convert BCM_Modes into Tag in the same measurements and how to do it?I have to group the vehicle_speed by this commandmodes. I am new to the Flux completely. Please help me with this

Hello @nagashree,
The best way to do this would be to delete and rewrite your data correctly using the same method you used to write your data the first time.
You can still group by fields.

Or you can follow this:

But your old data will still exist. So you’re not exactly replacing in this example. You’re just transforming with flux and writing data with flux.