In VSCode there is no debugger active for openHAB yet 
but I think you don’t need it as openHAB does online code checking.
In question of logs: Please take a look at /var/log/openhab2/openhab.log. There should be some lines about influxDB persistence Service.
You can set the log level for influxDB by using the karaf console:
log:set DEBUG org.openhab.persistence.influxdb
the default level would be
log:set DEFAULT org.openhab.persistence.influxdb
There is also a TRACE level if DEBUG will not suffice.