o.k., from my setup, for InfluxDB based persistence, but you can adapt this to JDBC based persistence very easily:
Number Terasse_Sensebox_Luminance "Terasse Light Level [%.1f lx]" <light> (Weather, gInflux)
the important part is the “(gInflux)” group membership in the item.
Then, in persistence/influxdb.persist:
gInflux* : strategy = everyChange, everyHour
gInfluxDaily* : strategy = everyChange, everyDay
Here, the important part is the “*” after the group name. I missed it in my first configurations, and it took me ages to find the simple syntax error.
Then, in services/influxdb.cfg,
See also the threads: