Turns out that there are more than zero users that are upgrading from
old databases. I think we probably want to support this for now.
Tested against database in https://github.com/ppy/osu/discussions/16700
and one other I had locally, both work correctly.
Closes#16651.
When a ruleset is not available, the `Find` call would return null. When
a null is passed to the constructor, `BeatmapInfo` would create an "osu"
ruleset, which tries to get stored to realm and fails on duplicate
primary key.
Probably need to add better safeties against this (or change that
constructor...) but this will fix the migration process.
Probably not serious enough to pull the build. This only affects
rulesets like karaoke which have custom beatmaps.
There's no real way to recover these unless we want to start importing
rulesets into realm. And that seems counter productive. This can only
happen if users don't have the dll present any more, and it was removed
far before realm was tracking rulesets (else it would have an
`Available=0` entry in realm to match).
This helps slightly with performance, allows better monitoring via realm
studio, but most importantly greatly reduces filesize.
fully compacted: 109M
transaction size 100: 115M
transaction size 1000: 123M
transaction size 10000: 164M
single transaction: 183M
With a transaction size of 100 there is a performance reduction, so 1000
seems to be the best middle-ground.
This really shouldn't have much effect as it will be run in the first
`Update` method and is probably a noop (we are already pointing to the
newest version due to just performing writes), but seems like a safe addition.
In general `Realm.Refresh()` only really does anything when there's multithreaded
usage and notifications to be sent.