[Bug]: PostgreSQL duplicate key value violates unique constraint "oc_filecache_extended"

⚠️ 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

2026-06-24 06:48:09.658 CEST [336893] ERROR:  duplicate key value violates unique constraint "oc_filecache_extended_pkey"
2026-06-24 06:48:09.658 CEST [336893] DETAIL:  Key (fileid)=(1044313) already exists.
2026-06-24 06:48:09.658 CEST [336893] STATEMENT:  INSERT INTO "oc_filecache_extended" ("fileid", "creation_time") VALUES($1, $2)
2026-06-24 06:48:09.774 CEST [336893] ERROR:  duplicate key value violates unique constraint "oc_filecache_extended_pkey"
2026-06-24 06:48:09.774 CEST [336893] DETAIL:  Key (fileid)=(1044312) already exists.
2026-06-24 06:48:09.774 CEST [336893] STATEMENT:  INSERT INTO "oc_filecache_extended" ("fileid", "creation_time") VALUES($1, $2)
2026-06-24 07:48:10.357 CEST [356981] ERROR:  duplicate key value violates unique constraint "oc_filecache_extended_pkey"
2026-06-24 07:48:10.357 CEST [356981] DETAIL:  Key (fileid)=(1044313) already exists.
2026-06-24 07:48:10.357 CEST [356981] STATEMENT:  INSERT INTO "oc_filecache_extended" ("fileid", "creation_time") VALUES($1, $2)
2026-06-24 07:48:10.456 CEST [356981] ERROR:  duplicate key value violates unique constraint "oc_filecache_extended_pkey"
2026-06-24 07:48:10.456 CEST [356981] DETAIL:  Key (fileid)=(1044312) already exists.
2026-06-24 07:48:10.456 CEST [356981] STATEMENT:  INSERT INTO "oc_filecache_extended" ("fileid", "creation_time") VALUES($1, $2)

Issue is causing high iostat to SSD and RAM usage from PostgreSQL.
Host is nearly not usable any more due to heavy load.

What has been done so far:

cleanup DB - delete from table or truncate table oc_filecache_extended
check and adopted mount settings for btrfs; chattr +C for databasefile
disabled and uninstalled Memories App
disabled and uninstalled Group Folders App
Other information
Host OS
Debian 12 bookworm: 6.1.174-1 (2026-05-26) x86_64 GNU/Linux
Nextcloud AIO: NC 33.0.5
PostgreSQL 18.4

Docker info

Client: Docker Engine - Community
 Version:    29.6.0
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.34.1
    Path:     /usr/libexec/docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v5.1.4
    Path:     /usr/libexec/docker/cli-plugins/docker-compose

Server:
 Containers: 13
  Running: 12
  Paused: 0
  Stopped: 1
 Images: 13
 Server Version: 29.6.0
 Storage Driver: overlay2
  Backing Filesystem: btrfs
  Supports d_type: true
  Using metacopy: false
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: systemd
 Cgroup Version: 2
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
 CDI spec directories:
  /etc/cdi
  /var/run/cdi
 Swarm: inactive
 Runtimes: runc io.containerd.runc.v2
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: e53c7c1516c3b2bff98eb76f1f4117477e6f4e66
 runc version: v1.3.6-0-g491b69ba
 init version: de40ad0
 Security Options:
  apparmor
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 6.1.0-49-amd64
 Operating System: Debian GNU/Linux 12 (bookworm)
 OSType: linux
 Architecture: x86_64
 CPUs: 4
 Total Memory: 15.37GiB
 Name: morpheus
 ID: d7c93caa-e386-48f0-88c1-c9879f0afbee
 Docker Root Dir: /data/docker
 Debug Mode: false
 Experimental: false
 Insecure Registries:
  ::1/128
  127.0.0.0/8
 Live Restore Enabled: false
 Firewall Backend: iptables
  EnableUserlandProxy: true
  UserlandProxyPath: /usr/bin/docker-proxy

Steps to reproduce

1. Start Nextcloud AIO
2. Wait, no interaction at, no file upload or download, ...
3. Have a look to database logs; iostat; RAM usage; postgres process

Expected behavior

no key value violations

Nextcloud Server version

33

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.3

Web server

Apache (supported)

Database engine version

PostgreSQL

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

None

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

{
    "system": {
        "one-click-instance": true,
        "one-click-instance.user-limit": 100,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "apps_paths": [
            {
                "path": "\/var\/www\/html\/apps",
                "url": "\/apps",
                "writable": false
            },
            {
                "path": "\/var\/www\/html\/custom_apps",
                "url": "\/custom_apps",
                "writable": true
            }
        ],
        "appsallowlist": false,
        "check_data_directory_permissions": false,
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "password": "***REMOVED SENSITIVE VALUE***",
            "port": 6379,
            "timeout": 3,
            "read_timeout": 10
        },
        "overwritehost": "cloud.vierviertel.org",
        "overwriteprotocol": "https",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "localhost",
            "cloud.vierviertel.org"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "pgsql",
        "version": "33.0.5.1",
        "overwrite.cli.url": "https:\/\/cloud.vierviertel.org\/",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "maintenance": false,
        "maintenance_window_start": 100,
        "updatedirectory": "\/nc-updater",
        "loglevel": 2,
        "log_type": "file",
        "logfile": "\/var\/www\/html\/data\/nextcloud.log",
        "log_rotate_size": "104857600",
        "log.condition": {
            "apps": [
                "admin_audit"
            ]
        },
        "preview_max_x": 1024,
        "preview_max_y": 1024,
        "jpeg_quality": 60,
        "enabledPreviewProviders": {
            "0": "OC\\Preview\\Imaginary",
            "1": "OC\\Preview\\TXT",
            "2": "OC\\Preview\\OpenDocument",
            "3": "OC\\Preview\\Movie",
            "4": "OC\\Preview\\Krita",
            "5": "OC\\Preview\\ImaginaryPDF",
            "6": "OC\\Preview\\HEIC",
            "7": "OC\\Preview\\TIFF",
            "8": "OC\\Preview\\ImaginaryPDF",
            "9": "OC\\Preview\\Image",
            "10": "OC\\Preview\\ImaginaryPDF",
            "23": "OC\\Preview\\ImaginaryPDF"
        },
        "enable_previews": true,
        "upgrade.disable-web": true,
        "mail_smtpmode": "smtp",
        "trashbin_retention_obligation": "auto, 7",
        "versions_retention_obligation": "auto, 30",
        "activity_expire_days": "30",
        "simpleSignUpLink.shown": false,
        "share_folder": "\/Shared",
        "one-click-instance.link": "https:\/\/nextcloud.com\/all-in-one\/",
        "upgrade.cli-upgrade-link": "https:\/\/github.com\/nextcloud\/all-in-one\/discussions\/2726",
        "allow_local_remote_servers": true,
        "davstorage.request_timeout": 3600,
        "htaccess.RewriteBase": "\/",
        "dbpersistent": false,
        "files_external_allow_create_new_local": false,
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "preview_imaginary_url": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpsecure": "ssl",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": 1,
        "mail_smtpport": "465",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "twofactor_enforced": "true",
        "twofactor_enforced_groups": [
            "home"
        ],
        "twofactor_enforced_excluded_groups": [],
        "default_locale": "de_AT",
        "default_phone_region": "AT",
        "preview_imaginary_key": "***REMOVED SENSITIVE VALUE***",
        "auth.bruteforce.protection.enabled": true,
        "ratelimit.protection.enabled": true,
        "documentation_url.server_logs": "https:\/\/github.com\/nextcloud\/all-in-one\/discussions\/5425",
        "memories.db.triggers.fcu": true,
        "memories.exiftool": "\/var\/www\/html\/custom_apps\/memories\/bin-ext\/exiftool-amd64-musl",
        "memories.vod.path": "\/var\/www\/html\/custom_apps\/memories\/bin-ext\/go-vod-amd64",
        "memories.vod.ffmpeg": "\/usr\/bin\/ffmpeg",
        "memories.vod.ffprobe": "\/usr\/bin\/ffprobe",
        "memories.gis_type": 2,
        "updatechecker": false,
        "serverid": 445,
        "log_type_audit": "file",
        "logfile_audit": "\/var\/www\/html\/data\/audit.log",
        "app_install_overwrite": [],
        "backgroundjobs": "OC\\BackgroundJob\\Cron",
        "update_channel": "stable",
        "memories.cache_dir": "\/mnt\/ncdata\/memories_cache",
        "DOMAIN": "cloud.vierviertel.org",
        "AIO_VERSION": "v13.2.1"
    }
}

List of activated Apps

Enabled:
  - activity: 6.0.0
  - admin_audit: 1.23.0
  - app_api: 33.0.0
  - bruteforcesettings: 6.0.0
  - calendar: 6.5.0
  - circles: 33.0.0
  - cloud_federation_api: 1.17.0
  - comments: 1.23.0
  - contacts: 8.7.1
  - dashboard: 7.13.0
  - dav: 1.36.0
  - federatedfilesharing: 1.23.0
  - federation: 1.23.0
  - files: 2.5.0
  - files_antivirus: 6.3.0
  - files_downloadlimit: 5.1.0
  - files_pdfviewer: 6.0.0
  - files_reminders: 1.6.0
  - files_sharing: 1.25.2
  - files_trashbin: 1.23.0
  - files_versions: 1.26.0
  - firstrunwizard: 6.0.0
  - integration_google: 4.4.0
  - logreader: 6.0.0
  - lookup_server_connector: 1.21.0
  - metavox: 2.2.0
  - nextcloud-aio: 0.8.0
  - nextcloud_announcements: 5.0.0
  - notes: 6.0.0
  - notifications: 6.0.0
  - notify_push: 1.3.3
  - oauth2: 1.21.0
  - password_policy: 5.0.0
  - photos: 6.0.0
  - previewgenerator: 5.13.0
  - privacy: 5.0.0
  - profile: 1.2.0
  - provisioning_api: 1.23.0
  - recommendations: 6.0.0
  - related_resources: 4.0.0
  - richdocuments: 10.2.0
  - serverinfo: 5.0.0
  - settings: 1.16.0
  - sharebymail: 1.23.0
  - support: 5.0.0
  - survey_client: 5.0.0
  - suspicious_login: 11.0.0
  - systemtags: 1.23.0
  - tasks: 0.17.1
  - text: 7.0.1
  - theming: 2.8.0
  - twofactor_backupcodes: 1.22.0
  - twofactor_totp: 15.0.0
  - updatenotification: 1.23.0
  - user_status: 1.13.0
  - viewer: 6.0.0
  - weather_status: 1.13.0
  - webhook_listeners: 1.5.0
  - workflowengine: 2.15.0
Disabled:
  - contactsinteraction: 1.14.1 (installed 1.9.0)
  - encryption: 2.21.0 (installed 2.16.0)
  - files_external: 1.25.1
  - twofactor_nextcloud_notification: 7.0.0
  - user_ldap: 1.24.0

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

Warnung no app in context Capabilities of OCA\Theming\Capabilities took 0.46 seconds to generate. 25.06.2026,17:38:54

Warnung no app in context Capabilities of OCA\Theming\Capabilities took 0.47 seconds to generate. 
25.06.2026, 17:38:47

Additional info

It is a Nextcloud AIO installation; I opened a ticket for AIO but I was asked to open a ticket here.

Start with the repeated PostgreSQL INSERT statements for oc_filecache_extended and the reported file IDs, then trace which Nextcloud activity causes them during the idle reproduction steps. Review the listed Nextcloud 33.0.5 configuration and enabled apps while reproducing the load. Done means identifying and preventing the repeated duplicate-key errors without requiring table deletion or truncation.