perf(db): Sort data for IN before chunking

[ChristophWurst]

Summary

Nextcloud sends chunks of DELETE FROM oc_filecache WHERE parentid IN (....long list...) and sometimes MariaDB does not seem to pick up the index. Apparently this may happen when the query analyzer thinks it's cheaper to scan the table than to traverse the index. If we put the data of the chunks closer together, we can hopefully convince the db that the index is the faster choice.

@juliushaertl @nickvergessen as it was suggested to us.

I don't know how to trigger this code with lots of data so this is more or less untested.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[Altahrim]

I didn't knew the trick to sort items. The other one is to use smaller chunks.

[come-nc]

@Altahrim Is that related to the big folder deletion&restore we looked into together? Would it help with the deadlock there?

[nickvergessen]

Would it help with the deadlock there?

Could, as that is also the direction where we are coming from

[ChristophWurst]

/backport to stable29

[ChristophWurst]

/backport to stable28

[ChristophWurst]

/backport to stable27