How to write values into InfluxDB 1.8.10?

[francwalter]

Hallo
I just installed this great tool to read my old watermeter which has not any electronics.
The reading is working, but now I want to add the data to my InfluxDB 1.8.10 on my Raspberry Pi 3B+ in my local network.
But the parameters are not clear to me. The help in the docs is small.
And the hover-help in the configuration is not clear enough for me.

How to put just the main value into the influxdb?
I mean these settings in Settings > Configuration:

What to put into "Measurement" and "Field"?

I just need the main value (wassermesser/main/value) and the corresponding timestamp in my InfluxDB.
I created a database "wassermesser" in my influxdb but there is after a while not any value. I dont see any logs where I could see what is missing.
MQTT is working though, with just this settings:

and I can see the value in MQTT Explorer:

Can someone point me to the solution?
Thanks. franks

[francwalter]

OK then, found it myself:

The settings are just the table and the field name.
I found it, because suddenly there was a value in my db.

To begin new from scratch I deleted the old database (wassermesser) and created a new one "wasserzaehler".
Now I have already two values in it:

[2025-08-29_14.17]root@raspberrypi:~#influx
Connected to http://localhost:8086 version 1.8.10
InfluxDB shell version: 1.8.10
> drop database wassermesser
> show databases
name: databases
name
----
_internal
stromzaehler
bkw
> create database wasserzaehler
> show databases
name: databases
name
----
_internal
stromzaehler
bkw
wasserzaehler
> use wasserzaehler
Using database wasserzaehler
> show series
key
---
zaehlerstand
...
...
> precision rfc3339
> select * from zaehlerstand
name: zaehlerstand
time                 kubikmeter
----                 ----------
2025-08-29T12:24:52Z 0.5698
2025-08-29T12:44:52Z 0.5698
2025-08-29T12:49:52Z 0.5698

I have some difficulties to get the exact values, at the moment two of my analog ROI are not that accurate:

As to see, it is not 0.5698 but 0.5657 but never mind, will live with it. It is only liter and 0.1 liter so not much problem if wrong.
The only thing is, when its less then the previous value, it wont write to db because of error.