Persistant group items not working?

not sure if there is another thing I have missed , I have created a persistence group in my config
I don’t see entry in my items table even after restart of openhab.

Q2: if I using in multiple items file do I put Group in all files or just one?

dbChangeStart: strategy = everyChange, restoreOnStartup

items file
Group computers
Group dbChangeStart
Switch work432070L (computers,dbChangeStart) { channel=“network:pingdevice:work432070L:online” }


will persist only the state of the Group.
You Group doesn’t appear to have any state defined to be recorded.
Did you mean to use
to record all member states, as defined in docs?

Create each Item only once. Groups are Items too.

hmm I’m still not getting it or something is missing

Switch work432070L (computers, dbChange) { channel=“network:pingdevice:work432070L:online” }

dbChange* : strategy = everyChange

I can see the state change but no output to database.

2021-10-16 08:47:10.197 [INFO ] [openhab.event.ItemUpdatedEvent      ] - Item 'work432070L' has been updated.
2021-10-16 08:47:10.213 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'work432070L' changed from NULL to ON

footnote: changed refreshInterval to 1 min (from 1hour) and mysteriously item appeared in DB

Thing network:pingdevice:work432070L [ hostname=“”, refreshInterval=60000]