Yes, or you can just put
* to represent ALL Items. If you look at the mapdb.persist file on the link I provided you will see that is what I did.
* : strategy = everyChange, restoreOnStartup
That means save every change to all Items and restore their values on startup.
Every minute is way overkill for MapDB. All you really need is everyChange.
However, if there are Items you want to exclude from restoreOnStartup you will need to list each of your groups separately.
All persist files use the same syntax.
That is correct. MapDB doesn't have the same limitation to numerical data that rrd4j does.
The main point of the post I linked to above is to create three or four new groups, one for each of the different ways you want to persist. For example:
Then just put those Groups into your .persist files where appropriate (e.g. mapdb.persist would be
gRestoreOnStartup* : everyChange, restoreOnStartup and rrd4j would be
gChart* : everyChange, everyMinute and so on). Then just assign your Items to the different groups as needed. If you want to do a blanket restoreOnStartup on all Items you don't need the first Group name, just put * in the mapdb.persist file.