Add index for classification attribute

[akhil1508]

• Resolves: # [Bug]: Query on calendarobjects by classification takes too long as it is not indexed #35136

Summary

• Added a migration to add an index for the "classification" column of the "calendarobjects" table

TODO

• ...

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)

[kesselb]

Thank you 👍

[tcitworld]

You also need to bump the app version in apps/dav/appinfo/info.xml so that the migrations are executed.

[tcitworld]

How long did creating the index took on your database? If it's too much we can move it to the dedicated missing indexes command (see for instance #33405)

[akhil1508]

@tcitworld It took 14 seconds to create the index on a database with 1 million entries in the calendarobjects table

[akhil1508]

@tcitworld Bumped from 1.25.0 to 1.25.1

[akhil1508]

@ALL it automatically requested review while I was trying to squash commits.. sorry :(

@kesselb I've tried squashing with different methods and none of them work as there are multiple merge commits from master in this one's history. Is it okay for you if I open PR in a new branch instead?

[susnux]

@akhil1508 it should work with:

git remote add upstream https://github.com/nextcloud/server.git
git fetch upstream
git rebase -i upstream/master

then mark all of you commits as "s" (for squash) and it should work.

[akhil1508]

@susnux I did as you suggested and force-pushed, now there are 33 changes instead of 3 changes 🤔

[tcitworld]

@akhil1508 Is the « Allow edits by maintainers » checkbox checked on the sidebar? Seems I can't force push to fix things.

[akhil1508]

@tcitworld Seems I cannot do that as this PR is made from a fork under an organization :(

As per https://github.com/orgs/community/discussions/5634

[tcitworld]

Replacement PR at #41111

[akhil1508]

@tcitworld Thanks for the replacement PR :)