[Bug]: Exception: Database error when running migration 33000Date20251023120529 for app core

[keestux]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

I'm upgrading from 32.0.8 to 33.0.2. One of the final steps is to run occ upgrade -vvv. This results in the following error

2026-04-14T14:24:25+00:00 Setting log level to debug
2026-04-14T14:24:25+00:00 Repair step: Repair MySQL collation
2026-04-14T14:24:25+00:00 Repair info: All tables already have the correct collation -> nothing to do
2026-04-14T14:24:25+00:00 Repair step: Copy data from accounts table when migrating from ownCloud
2026-04-14T14:24:25+00:00 Repair step: Drop account terms table when migrating from ownCloud
2026-04-14T14:24:25+00:00 Updating database schema
2026-04-14T14:24:25+00:00 Exception: Database error when running migration 33000Date20251023120529 for app core
An index with name "unique_bucket_store" was already defined on table "oc_preview_locations".
2026-04-14T14:24:25+00:00 Update failed
2026-04-14T14:24:25+00:00 Maintenance mode is kept active
2026-04-14T14:24:25+00:00 Resetting log level

Steps to reproduce

1. start with a working nextcloud 32
2. install 33 by unpacking the tar
3. update all apps
4. run the upgrade step from the command line, basically doing occ upgrade

Expected behavior

I've done several upgrades in the past, 28->29, 29->30, 30->31, 31->32. In each case the upgrade succeeded without an error and Nextcloud came up normally.

Nextcloud Server version

33

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.3

Web server

Apache (supported)

Database engine version

MariaDB

Is this bug present after an update or on a fresh install?

Upgraded to a MAJOR version (ex. 31 to 32)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

# sudo -u www-data php /var/www/nextcloud/occ config:list system
Nextcloud or one of the apps require upgrade - only a limited number of commands are available
You may use your browser or the occ upgrade command to do the upgrade
{
    "system": {
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "localhost",
            "test-nextcloud.ghs.nl"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "33.0.2.2",
        "overwrite.cli.url": "https:\/\/test-nextcloud.ghs.nl",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "has_internet_connection": false,
        "appstoreenabled": false,
        "default_phone_region": "NL",
        "memcache.local": "\\OC\\Memcache\\APCu",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 0,
            "dbindex": 0,
            "password": "***REMOVED SENSITIVE VALUE***",
            "timeout": 1.5
        },
        "ldapProviderFactory": "OCA\\User_LDAP\\LDAPProviderFactory",
        "maintenance": true,
        "loglevel": 2,
        "mail_smtpmode": "smtp",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "maintenance_window": 2,
        "maintenance_window_start": 2,
        "logfile": "\/nextcloud-logs\/nextcloud.log",
        "trashbin_retension_obligation": "auto,30",
        "data-fingerprint": "6984ebde599b02e2b312d76cb597a561"
    }
}

List of activated Apps

# sudo -u www-data php /var/www/nextcloud/occ app:list
Nextcloud or one of the apps require upgrade - only a limited number of commands are available
You may use your browser or the occ upgrade command to do the upgrade
Enabled:
  - activity: 5.0.0
  - admin_audit: 1.22.0
  - app_api: 32.0.0
  - bruteforcesettings: 5.0.0
  - calendar: 6.2.2
  - circles: 32.0.0
  - cloud_federation_api: 1.16.0
  - comments: 1.22.0
  - contacts: 8.3.7
  - contactsinteraction: 1.13.1
  - dashboard: 7.12.0
  - dav: 1.34.2
  - federatedfilesharing: 1.22.0
  - federation: 1.22.0
  - files: 2.4.0
  - files_downloadlimit: 5.0.0
  - files_external: 1.24.1
  - files_pdfviewer: 5.0.0
  - files_sharing: 1.24.1
  - files_trashbin: 1.22.0
  - files_versions: 1.25.0
  - firstrunwizard: 5.0.0
  - logreader: 5.0.0
  - lookup_server_connector: 1.20.0
  - nextcloud_announcements: 4.0.0
  - notes: 4.13.1
  - notifications: 5.0.0
  - oauth2: 1.20.0
  - password_policy: 4.0.0
  - photos: 5.0.0
  - privacy: 4.0.0
  - profile: 1.1.0
  - provisioning_api: 1.22.0
  - recommendations: 5.0.0
  - related_resources: 3.0.0
  - richdocuments: 9.0.5
  - richdocumentscode: 25.4.904
  - serverinfo: 4.0.0
  - settings: 1.15.1
  - sharebymail: 1.22.0
  - support: 4.0.0
  - systemtags: 1.22.0
  - text: 6.0.1
  - theming: 2.7.0
  - twofactor_backupcodes: 1.21.0
  - twofactor_totp: 14.0.0
  - user_ldap: 1.23.0
  - user_status: 1.12.0
  - viewer: 5.0.0
  - webhook_listeners: 1.3.0
  - workflowengine: 2.14.0
Disabled:
  - encryption: 2.21.0 (installed 2.6.0)
  - files_reminders: 1.6.0 (installed 1.0.0)
  - survey_client: 5.0.0 (installed 1.15.0)
  - suspicious_login: 11.0.0
  - testing: 1.23.0
  - twofactor_nextcloud_notification: 7.0.0
  - updatenotification: 1.23.0 (installed 1.14.0)
  - weather_status: 1.13.0 (installed 1.7.0)

Nextcloud Signing status

Nextcloud Logs

Additional info

No response

[keestux]

As I wrote in #58591, the Version33000Date20250819110529.php migration is supposed to create three new tables. But none of the tables are present after running upgrade.

[keestux]

Correction/addition to my previous comment.

The oc_preview_locations and the unique_bucket_store is present, but upgrade still wants to run that migration step.

If I completely wipe the database and restore it from backup and then run upgrade it succeeds.