Error MariaDB SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous

Cisco30 · August 24, 2026, 9:16am

The Basics

Nextcloud Server version (e.g., 29.x.x):
- 34.0.3
Operating system and version (e.g., Ubuntu 24.04):
- Debian 13
Web server and version (e.g, Apache 2.4.25):
- Apache 2
Reverse proxy and version _(e.g. nginx 1.27.2)
- ``
PHP version (e.g, 8.3):
- PHP 8.5.9
Is this the first time you’ve seen this error? (Yes / No):
- Yes
When did this problem seem to first start?
- Following a Nextcloud update
Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.)
- Bare metal
Are you using CloudfIare, mod_security, or similar? (Yes / No)
- No

Summary of the issue you are facing:

I have been encountering this error since a Nextcloud update; I also noticed that the preview generator causes errors when generating thumbnails.

Steps to replicate it (hint: details matter!):

The error occurs in the Photos tab; browsing through the photos triggers errors.

Log entries

Nextcloud

Please provide the log entries from your Nextcloud log that are generated during the time of problem (via the Copy raw option from Administration settings->Logging screen or from your nextcloud.log located in your data directory). Feel free to use a pastebin/gist service if necessary.

{"reqId":"t61q0S0C0SBgrz5lW6hl","level":3,"time":"2026-08-24T09:10:03+00:00","remoteAddr":"","user":"--","app":"core","method":"","url":"--","scriptName":"/var/www/nextcloud/cron.php","message":"Error while running background job OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob (id: 118296160525254657, arguments: null)","userAgent":"--","version":"34.0.3.2","occ_command":["/var/www/nextcloud/cron.php"],"exception":{"Exception":"OC\\DB\\Exceptions\\DbalException","Message":"An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous","Code":1052,"Trace":[{"file":"/var/www/nextcloud/lib/private/DB/ConnectionAdapter.php","line":60,"function":"wrap","class":"OC\\DB\\Exceptions\\DbalException","type":"::"},{"file":"/var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php","line":261,"function":"executeQuery","class":"OC\\DB\\ConnectionAdapter","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":276,"function":"executeQuery","class":"OC\\DB\\QueryBuilder\\QueryBuilder","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":382,"function":"findOneQuery","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php","line":250,"function":"findEntity","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":605,"function":"getPreviewForSpecification","class":"OC\\Preview\\Db\\PreviewMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":566,"function":"savePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":184,"function":"generatePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/PreviewManager.php","line":203,"function":"generatePreviews","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":160,"function":"generatePreviews","class":"OC\\PreviewManager","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":141,"function":"processFile","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":110,"function":"processRow","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":73,"function":"startProcessing","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php","line":61,"function":"preGenerate","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/Job.php","line":50,"function":"run","class":"OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php","line":86,"function":"start","class":"OCP\\BackgroundJob\\Job","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":204,"function":"start","class":"OCP\\BackgroundJob\\TimedJob","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":107,"function":"runCli","class":"OC\\Core\\Service\\CronService","type":"->"},{"file":"/var/www/nextcloud/cron.php","line":52,"function":"run","class":"OC\\Core\\Service\\CronService","type":"->"}],"File":"/var/www/nextcloud/lib/private/DB/Exceptions/DbalException.php","Line":50,"Previous":{"Exception":"Doctrine\\DBAL\\Exception\\NonUniqueFieldNameException","Message":"An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous","Code":1052,"Trace":[{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php","line":1976,"function":"convert","class":"Doctrine\\DBAL\\Driver\\API\\MySQL\\ExceptionConverter","type":"->"},{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php","line":1918,"function":"handleDriverException","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php","line":1111,"function":"convertExceptionDuringQuery","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/Connection.php","line":427,"function":"executeQuery","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/ConnectionAdapter.php","line":57,"function":"executeQuery","class":"OC\\DB\\Connection","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php","line":261,"function":"executeQuery","class":"OC\\DB\\ConnectionAdapter","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":276,"function":"executeQuery","class":"OC\\DB\\QueryBuilder\\QueryBuilder","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":382,"function":"findOneQuery","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php","line":250,"function":"findEntity","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":605,"function":"getPreviewForSpecification","class":"OC\\Preview\\Db\\PreviewMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":566,"function":"savePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":184,"function":"generatePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/PreviewManager.php","line":203,"function":"generatePreviews","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":160,"function":"generatePreviews","class":"OC\\PreviewManager","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":141,"function":"processFile","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":110,"function":"processRow","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":73,"function":"startProcessing","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php","line":61,"function":"preGenerate","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/Job.php","line":50,"function":"run","class":"OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php","line":86,"function":"start","class":"OCP\\BackgroundJob\\Job","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":204,"function":"start","class":"OCP\\BackgroundJob\\TimedJob","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":107,"function":"runCli","class":"OC\\Core\\Service\\CronService","type":"->"},{"file":"/var/www/nextcloud/cron.php","line":52,"function":"run","class":"OC\\Core\\Service\\CronService","type":"->"}],"File":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/API/MySQL/ExceptionConverter.php","Line":74,"Previous":{"Exception":"Doctrine\\DBAL\\Driver\\PDO\\Exception","Message":"SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous","Code":1052,"Trace":[{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php","line":132,"function":"new","class":"Doctrine\\DBAL\\Driver\\PDO\\Exception","type":"::"},{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/Middleware/AbstractStatementMiddleware.php","line":69,"function":"execute","class":"Doctrine\\DBAL\\Driver\\PDO\\Statement","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/Middleware/ConnectionActivityStatement.php","line":26,"function":"execute","class":"Doctrine\\DBAL\\Driver\\Middleware\\AbstractStatementMiddleware","type":"->"},{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php","line":1104,"function":"execute","class":"OC\\DB\\Middleware\\ConnectionActivityStatement","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/Connection.php","line":427,"function":"executeQuery","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/ConnectionAdapter.php","line":57,"function":"executeQuery","class":"OC\\DB\\Connection","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php","line":261,"function":"executeQuery","class":"OC\\DB\\ConnectionAdapter","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":276,"function":"executeQuery","class":"OC\\DB\\QueryBuilder\\QueryBuilder","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":382,"function":"findOneQuery","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php","line":250,"function":"findEntity","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":605,"function":"getPreviewForSpecification","class":"OC\\Preview\\Db\\PreviewMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":566,"function":"savePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":184,"function":"generatePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/PreviewManager.php","line":203,"function":"generatePreviews","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":160,"function":"generatePreviews","class":"OC\\PreviewManager","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":141,"function":"processFile","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":110,"function":"processRow","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":73,"function":"startProcessing","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php","line":61,"function":"preGenerate","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/Job.php","line":50,"function":"run","class":"OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php","line":86,"function":"start","class":"OCP\\BackgroundJob\\Job","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":204,"function":"start","class":"OCP\\BackgroundJob\\TimedJob","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":107,"function":"runCli","class":"OC\\Core\\Service\\CronService","type":"->"},{"file":"/var/www/nextcloud/cron.php","line":52,"function":"run","class":"OC\\Core\\Service\\CronService","type":"->"}],"File":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Exception.php","Line":24,"Previous":{"Exception":"PDOException","Message":"SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous","Code":"23000","Trace":[{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php","line":130,"function":"execute","class":"PDOStatement","type":"->"},{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/Middleware/AbstractStatementMiddleware.php","line":69,"function":"execute","class":"Doctrine\\DBAL\\Driver\\PDO\\Statement","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/Middleware/ConnectionActivityStatement.php","line":26,"function":"execute","class":"Doctrine\\DBAL\\Driver\\Middleware\\AbstractStatementMiddleware","type":"->"},{"file":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php","line":1104,"function":"execute","class":"OC\\DB\\Middleware\\ConnectionActivityStatement","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/Connection.php","line":427,"function":"executeQuery","class":"Doctrine\\DBAL\\Connection","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/ConnectionAdapter.php","line":57,"function":"executeQuery","class":"OC\\DB\\Connection","type":"->"},{"file":"/var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php","line":261,"function":"executeQuery","class":"OC\\DB\\ConnectionAdapter","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":276,"function":"executeQuery","class":"OC\\DB\\QueryBuilder\\QueryBuilder","type":"->"},{"file":"/var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php","line":382,"function":"findOneQuery","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php","line":250,"function":"findEntity","class":"OCP\\AppFramework\\Db\\QBMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":605,"function":"getPreviewForSpecification","class":"OC\\Preview\\Db\\PreviewMapper","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":566,"function":"savePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/Preview/Generator.php","line":184,"function":"generatePreview","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/lib/private/PreviewManager.php","line":203,"function":"generatePreviews","class":"OC\\Preview\\Generator","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":160,"function":"generatePreviews","class":"OC\\PreviewManager","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":141,"function":"processFile","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":110,"function":"processRow","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php","line":73,"function":"startProcessing","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php","line":61,"function":"preGenerate","class":"OCA\\PreviewGenerator\\Service\\PreGenerateService","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/Job.php","line":50,"function":"run","class":"OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob","type":"->"},{"file":"/var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php","line":86,"function":"start","class":"OCP\\BackgroundJob\\Job","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":204,"function":"start","class":"OCP\\BackgroundJob\\TimedJob","type":"->"},{"file":"/var/www/nextcloud/core/Service/CronService.php","line":107,"function":"runCli","class":"OC\\Core\\Service\\CronService","type":"->"},{"file":"/var/www/nextcloud/cron.php","line":52,"function":"run","class":"OC\\Core\\Service\\CronService","type":"->"}],"File":"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php","Line":130}}},"message":"Error while running background job OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob (id: 118296160525254657, arguments: null)","exception":"{\"class\":\"OC\\DB\\Exceptions\\DbalException\",\"message\":\"An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous\",\"code\":1052,\"file\":\"/var/www/nextcloud/lib/private/DB/Exceptions/DbalException.php:50\",\"trace\":\"#0 /var/www/nextcloud/lib/private/DB/ConnectionAdapter.php(60): OC\\DB\\Exceptions\\DbalException::wrap()\\n#1 /var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php(261): OC\\DB\\ConnectionAdapter->executeQuery()\\n#2 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(276): OC\\DB\\QueryBuilder\\QueryBuilder->executeQuery()\\n#3 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(382): OCP\\AppFramework\\Db\\QBMapper->findOneQuery()\\n#4 /var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php(250): OCP\\AppFramework\\Db\\QBMapper->findEntity()\\n#5 /var/www/nextcloud/lib/private/Preview/Generator.php(605): OC\\Preview\\Db\\PreviewMapper->getPreviewForSpecification()\\n#6 /var/www/nextcloud/lib/private/Preview/Generator.php(566): OC\\Preview\\Generator->savePreview()\\n#7 /var/www/nextcloud/lib/private/Preview/Generator.php(184): OC\\Preview\\Generator->generatePreview()\\n#8 /var/www/nextcloud/lib/private/PreviewManager.php(203): OC\\Preview\\Generator->generatePreviews()\\n#9 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(160): OC\\PreviewManager->generatePreviews()\\n#10 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(141): OCA\\PreviewGenerator\\Service\\PreGenerateService->processFile()\\n#11 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(110): OCA\\PreviewGenerator\\Service\\PreGenerateService->processRow()\\n#12 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(73): OCA\\PreviewGenerator\\Service\\PreGenerateService->startProcessing()\\n#13 /var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php(61): OCA\\PreviewGenerator\\Service\\PreGenerateService->preGenerate()\\n#14 /var/www/nextcloud/lib/public/BackgroundJob/Job.php(50): OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob->run()\\n#15 /var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php(86): OCP\\BackgroundJob\\Job->start()\\n#16 /var/www/nextcloud/core/Service/CronService.php(204): OCP\\BackgroundJob\\TimedJob->start()\\n#17 /var/www/nextcloud/core/Service/CronService.php(107): OC\\Core\\Service\\CronService->runCli()\\n#18 /var/www/nextcloud/cron.php(52): OC\\Core\\Service\\CronService->run()\\n#19 {main}\",\"previous\":{\"class\":\"Doctrine\\DBAL\\Exception\\NonUniqueFieldNameException\",\"message\":\"An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous\",\"code\":1052,\"file\":\"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/API/MySQL/ExceptionConverter.php:74\",\"trace\":\"#0 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php(1976): Doctrine\\DBAL\\Driver\\API\\MySQL\\ExceptionConverter->convert()\\n#1 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php(1918): Doctrine\\DBAL\\Connection->handleDriverException()\\n#2 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php(1111): Doctrine\\DBAL\\Connection->convertExceptionDuringQuery()\\n#3 /var/www/nextcloud/lib/private/DB/Connection.php(427): Doctrine\\DBAL\\Connection->executeQuery()\\n#4 /var/www/nextcloud/lib/private/DB/ConnectionAdapter.php(57): OC\\DB\\Connection->executeQuery()\\n#5 /var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php(261): OC\\DB\\ConnectionAdapter->executeQuery()\\n#6 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(276): OC\\DB\\QueryBuilder\\QueryBuilder->executeQuery()\\n#7 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(382): OCP\\AppFramework\\Db\\QBMapper->findOneQuery()\\n#8 /var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php(250): OCP\\AppFramework\\Db\\QBMapper->findEntity()\\n#9 /var/www/nextcloud/lib/private/Preview/Generator.php(605): OC\\Preview\\Db\\PreviewMapper->getPreviewForSpecification()\\n#10 /var/www/nextcloud/lib/private/Preview/Generator.php(566): OC\\Preview\\Generator->savePreview()\\n#11 /var/www/nextcloud/lib/private/Preview/Generator.php(184): OC\\Preview\\Generator->generatePreview()\\n#12 /var/www/nextcloud/lib/private/PreviewManager.php(203): OC\\Preview\\Generator->generatePreviews()\\n#13 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(160): OC\\PreviewManager->generatePreviews()\\n#14 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(141): OCA\\PreviewGenerator\\Service\\PreGenerateService->processFile()\\n#15 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(110): OCA\\PreviewGenerator\\Service\\PreGenerateService->processRow()\\n#16 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(73): OCA\\PreviewGenerator\\Service\\PreGenerateService->startProcessing()\\n#17 /var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php(61): OCA\\PreviewGenerator\\Service\\PreGenerateService->preGenerate()\\n#18 /var/www/nextcloud/lib/public/BackgroundJob/Job.php(50): OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob->run()\\n#19 /var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php(86): OCP\\BackgroundJob\\Job->start()\\n#20 /var/www/nextcloud/core/Service/CronService.php(204): OCP\\BackgroundJob\\TimedJob->start()\\n#21 /var/www/nextcloud/core/Service/CronService.php(107): OC\\Core\\Service\\CronService->runCli()\\n#22 /var/www/nextcloud/cron.php(52): OC\\Core\\Service\\CronService->run()\\n#23 {main}\",\"previous\":{\"class\":\"Doctrine\\DBAL\\Driver\\PDO\\Exception\",\"message\":\"SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous\",\"code\":1052,\"file\":\"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Exception.php:24\",\"trace\":\"#0 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php(132): Doctrine\\DBAL\\Driver\\PDO\\Exception::new()\\n#1 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/Middleware/AbstractStatementMiddleware.php(69): Doctrine\\DBAL\\Driver\\PDO\\Statement->execute()\\n#2 /var/www/nextcloud/lib/private/DB/Middleware/ConnectionActivityStatement.php(26): Doctrine\\DBAL\\Driver\\Middleware\\AbstractStatementMiddleware->execute()\\n#3 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php(1104): OC\\DB\\Middleware\\ConnectionActivityStatement->execute()\\n#4 /var/www/nextcloud/lib/private/DB/Connection.php(427): Doctrine\\DBAL\\Connection->executeQuery()\\n#5 /var/www/nextcloud/lib/private/DB/ConnectionAdapter.php(57): OC\\DB\\Connection->executeQuery()\\n#6 /var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php(261): OC\\DB\\ConnectionAdapter->executeQuery()\\n#7 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(276): OC\\DB\\QueryBuilder\\QueryBuilder->executeQuery()\\n#8 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(382): OCP\\AppFramework\\Db\\QBMapper->findOneQuery()\\n#9 /var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php(250): OCP\\AppFramework\\Db\\QBMapper->findEntity()\\n#10 /var/www/nextcloud/lib/private/Preview/Generator.php(605): OC\\Preview\\Db\\PreviewMapper->getPreviewForSpecification()\\n#11 /var/www/nextcloud/lib/private/Preview/Generator.php(566): OC\\Preview\\Generator->savePreview()\\n#12 /var/www/nextcloud/lib/private/Preview/Generator.php(184): OC\\Preview\\Generator->generatePreview()\\n#13 /var/www/nextcloud/lib/private/PreviewManager.php(203): OC\\Preview\\Generator->generatePreviews()\\n#14 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(160): OC\\PreviewManager->generatePreviews()\\n#15 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(141): OCA\\PreviewGenerator\\Service\\PreGenerateService->processFile()\\n#16 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(110): OCA\\PreviewGenerator\\Service\\PreGenerateService->processRow()\\n#17 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(73): OCA\\PreviewGenerator\\Service\\PreGenerateService->startProcessing()\\n#18 /var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php(61): OCA\\PreviewGenerator\\Service\\PreGenerateService->preGenerate()\\n#19 /var/www/nextcloud/lib/public/BackgroundJob/Job.php(50): OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob->run()\\n#20 /var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php(86): OCP\\BackgroundJob\\Job->start()\\n#21 /var/www/nextcloud/core/Service/CronService.php(204): OCP\\BackgroundJob\\TimedJob->start()\\n#22 /var/www/nextcloud/core/Service/CronService.php(107): OC\\Core\\Service\\CronService->runCli()\\n#23 /var/www/nextcloud/cron.php(52): OC\\Core\\Service\\CronService->run()\\n#24 {main}\",\"previous\":{\"class\":\"PDOException\",\"message\":\"SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous\",\"code\":\"23000\",\"file\":\"/var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php:130\",\"trace\":\"#0 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/PDO/Statement.php(130): PDOStatement->execute()\\n#1 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Driver/Middleware/AbstractStatementMiddleware.php(69): Doctrine\\DBAL\\Driver\\PDO\\Statement->execute()\\n#2 /var/www/nextcloud/lib/private/DB/Middleware/ConnectionActivityStatement.php(26): Doctrine\\DBAL\\Driver\\Middleware\\AbstractStatementMiddleware->execute()\\n#3 /var/www/nextcloud/3rdparty/doctrine/dbal/src/Connection.php(1104): OC\\DB\\Middleware\\ConnectionActivityStatement->execute()\\n#4 /var/www/nextcloud/lib/private/DB/Connection.php(427): Doctrine\\DBAL\\Connection->executeQuery()\\n#5 /var/www/nextcloud/lib/private/DB/ConnectionAdapter.php(57): OC\\DB\\Connection->executeQuery()\\n#6 /var/www/nextcloud/lib/private/DB/QueryBuilder/QueryBuilder.php(261): OC\\DB\\ConnectionAdapter->executeQuery()\\n#7 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(276): OC\\DB\\QueryBuilder\\QueryBuilder->executeQuery()\\n#8 /var/www/nextcloud/lib/public/AppFramework/Db/QBMapper.php(382): OCP\\AppFramework\\Db\\QBMapper->findOneQuery()\\n#9 /var/www/nextcloud/lib/private/Preview/Db/PreviewMapper.php(250): OCP\\AppFramework\\Db\\QBMapper->findEntity()\\n#10 /var/www/nextcloud/lib/private/Preview/Generator.php(605): OC\\Preview\\Db\\PreviewMapper->getPreviewForSpecification()\\n#11 /var/www/nextcloud/lib/private/Preview/Generator.php(566): OC\\Preview\\Generator->savePreview()\\n#12 /var/www/nextcloud/lib/private/Preview/Generator.php(184): OC\\Preview\\Generator->generatePreview()\\n#13 /var/www/nextcloud/lib/private/PreviewManager.php(203): OC\\Preview\\Generator->generatePreviews()\\n#14 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(160): OC\\PreviewManager->generatePreviews()\\n#15 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(141): OCA\\PreviewGenerator\\Service\\PreGenerateService->processFile()\\n#16 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(110): OCA\\PreviewGenerator\\Service\\PreGenerateService->processRow()\\n#17 /var/www/nextcloud/apps/previewgenerator/lib/Service/PreGenerateService.php(73): OCA\\PreviewGenerator\\Service\\PreGenerateService->startProcessing()\\n#18 /var/www/nextcloud/apps/previewgenerator/lib/BackgroundJob/PreviewJob.php(61): OCA\\PreviewGenerator\\Service\\PreGenerateService->preGenerate()\\n#19 /var/www/nextcloud/lib/public/BackgroundJob/Job.php(50): OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob->run()\\n#20 /var/www/nextcloud/lib/public/BackgroundJob/TimedJob.php(86): OCP\\BackgroundJob\\Job->start()\\n#21 /var/www/nextcloud/core/Service/CronService.php(204): OCP\\BackgroundJob\\TimedJob->start()\\n#22 /var/www/nextcloud/core/Service/CronService.php(107): OC\\Core\\Service\\CronService->runCli()\\n#23 /var/www/nextcloud/cron.php(52): OC\\Core\\Service\\CronService->run()\\n#24 {main}\"}}}}","CustomMessage":"Error while running background job OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob (id: 118296160525254657, arguments: null)"}}

Web Browser

If the problem is related to the Web interface, open your browser inspector Console and Network tabs while refreshing (reloading) and reproducing the problem. Provide any relevant output/errors here that appear.

Web server / Reverse Proxy

The output of your Apache/nginx/system log in /var/log/____:

192.168.1.254 - - [24/Aug/2026:11:09:37 +0200] "GET /push/ws HTTP/1.1" 101 4460 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "GET /ocs/v2.php/apps/terms_of_service/terms HTTP/1.1" 200 2494 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "PROPFIND /remote.php/dav/files/Boubou/Photo%20de%20Boubou/Dossier%20de%20t%C3%A9l%C3%A9versement/ HTTP/1.1" 207 1395 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "GET /ocs/v2.php/apps/guests/api/v1/groups HTTP/1.1" 200 994 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "PUT /ocs/v2.php/apps/user_status/api/v1/heartbeat?format=json HTTP/1.1" 200 949 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "GET /ocs/v2.php/apps/user_status/api/v1/user_status HTTP/1.1" 200 949 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "GET /contactsmenu/teams HTTP/1.1" 200 4905 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "POST /apps/notify_push/pre_auth HTTP/1.1" 200 841 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "GET /ocs/v2.php/apps/notifications/api/v2/notifications HTTP/1.1" 200 5039 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:45 +0200] "SEARCH /remote.php/dav/ HTTP/1.1" 207 412762 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"
192.168.1.254 - - [24/Aug/2026:11:10:46 +0200] "SEARCH /remote.php/dav/ HTTP/1.1" 207 488618 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36"

Configuration

Nextcloud

The output of occ config:list system or similar is best, but, if not possible, the contents of your config.php file from /path/to/nextcloud is fine (make sure to remove any identifiable information!):

    "system": {
        "serverid": 0,
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "cloud.tiboxs.com",
            "www.cloud.tiboxs.com",
            "[2a01:e0a:1014:5670:b696:91ff:fe1f:57c0]"
        ],
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "version": "34.0.3.2",
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "overwrite.cli.url": "https:\/\/cloud.tiboxs.com",
        "dbtype": "mysql",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": "0",
            "timeout": "0.0"
        },
        "installed": true,
        "default_phone_region": "FR",
        "htaccess.RewriteBase": "\/",
        "trashbin_retention_obligation": "auto, 30",
        "filelocking.enabled": "true",
        "knowledgebaseenabled": false,
        "activity_expire_days": 7,
        "skeletondirectory": "\/var\/www\/extra_nextcloud\/skeleton\/",
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "memcache.local": "\\OC\\Memcache\\Redis",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "mail_smtpmode": "smtp",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "587",
        "mail_smtpauth": true,
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "default_language": "fr",
        "default_locale": "fr_FR",
        "updater.release.channel": "stable",
        "check_for_working_htaccess": true,
        "check_data_directory_permissions": true,
        "login_form_autocomplete": false,
        "maintenance_window_start": 1,
        "maintenance": false,
        "integrity.check.disabled": false,
        "files.chunked_upload.max_size": 104857600,
        "twofactor_enforced": "true",
        "enable_previews": true,
        "enabledPreviewProviders": [
            "OC\\Preview\\BMP",
            "OC\\Preview\\GIF",
            "OC\\Preview\\JPEG",
            "OC\\Preview\\Krita",
            "OC\\Preview\\MarkDown",
            "OC\\Preview\\MP3",
            "OC\\Preview\\OpenDocument",
            "OC\\Preview\\PNG",
            "OC\\Preview\\TXT",
            "OC\\Preview\\XBitmap",
            "OC\\Preview\\Image",
            "OC\\Preview\\HEIC",
            "OC\\Preview\\TIFF",
            "OC\\Preview\\Movie",
            "OC\\Preview\\MP4",
            "OC\\Preview\\PDF",
            "OC\\Preview\\SVG"
        ],
        "preview_max_x": 1024,
        "preview_max_y": 1024,
        "preview_concurrency_all": 8,
        "preview_concurrency_new": 4,
        "preview_max_filesize_image": 200,
        "preview_max_memory": -1,
        "preview_ffmpeg_path": "\/usr\/bin\/ffmpeg",
        "theme": "",
        "loglevel": 2,
        "appcodechecker": true,
        "updatechecker": true,
        "has_internet_connection": true,
        "config_preset": 0,
        "twofactor_enforced_groups": [
            "admin",
            "Systeme"
        ],
        "twofactor_enforced_excluded_groups": [
            "Mes Amis",
            "Utilisateurs Nextcloud",
            "guest_app"
        ],
        "app_install_overwrite": [
            "theming_customcss"
        ],
        "defaultapp": "dashboard,files,photos,spreed,contacts,calendar,tasks,notes,office,passman,otpmanager,secrets,maps,cookbook,activity,announcementcenter",
        "mail_smtpstreamoptions": {
            "ssl": {
                "allow_self_signed": false,
                "verify_peer": true,
                "verify_peer_name": true

Apps

The output of occ app:list (if possible).

Enabled:
  - activity: 7.0.0
  - admin_audit: 1.24.0
  - announcementcenter: 7.5.0
  - appstore: 1.0.0
  - bruteforcesettings: 7.0.0
  - calendar: 6.5.4
  - cloud_federation_api: 1.18.0
  - comments: 1.24.0
  - contacts: 8.7.6
  - cookbook: 0.11.10-alpha1
  - dashboard: 7.14.0
  - dav: 1.40.0
  - drop_account: 3.0.0
  - encryption: 2.22.0
  - epubviewer: 1.9.7
  - external: 9.0.1
  - federatedfilesharing: 1.24.0
  - files: 2.6.0
  - files_accesscontrol: 5.0.0
  - files_downloadlimit: 5.2.0
  - files_external: 1.26.0
  - files_lock: 34.0.1
  - files_pdfviewer: 7.0.0-dev.0
  - files_reminders: 1.7.0
  - files_sharing: 1.26.0
  - files_trashbin: 1.24.0
  - files_versions: 1.27.0
  - firstrunwizard: 7.0.0-dev.0
  - guests: 4.9.0
  - impersonate: 5.0.0
  - logreader: 7.0.0
  - lookup_server_connector: 1.22.0
  - maps: 1.8.0
  - nextcloud_announcements: 6.0.0
  - notes: 6.0.2
  - notifications: 7.0.0-dev.1
  - notify_push: 1.4.0
  - oauth2: 1.22.0
  - office: 1.0.0
  - otpmanager: 1.2.2
  - ownershiptransfer: 1.5.0
  - passman: 2.6.1
  - password_policy: 6.0.0-dev.0
  - photos: 7.0.0
  - previewgenerator: 5.14.0
  - profile: 1.3.0
  - provisioning_api: 1.24.0
  - quota_warning: 1.24.0
  - registration: 3.0.0
  - richdocuments: 11.1.0
  - secrets: 3.0.6
  - serverinfo: 6.0.0
  - settings: 1.17.0
  - sharebymail: 1.24.0
  - sociallogin: 6.5.4
  - socialsharing_diaspora: 4.1.0
  - socialsharing_email: 4.1.0
  - socialsharing_facebook: 4.1.0
  - socialsharing_twitter: 4.1.0
  - spreed: 24.0.4
  - suspicious_login: 12.0.0-dev.0
  - tasks: 0.18.1
  - terms_of_service: 4.7.1
  - text: 8.0.0
  - theming: 2.9.0
  - theming_customcss: 1.21.0
  - twofactor_backupcodes: 1.23.0
  - twofactor_email: 3.4.2
  - twofactor_nextcloud_notification: 8.0.0
  - twofactor_totp: 16.0.0
  - unroundedcorners: 1.1.6
  - updatenotification: 1.24.0
  - user_retention: 1.17.0
  - user_status: 1.14.0
  - viewer: 7.0.0-dev.0
  - weather_status: 1.14.0
  - webhook_listeners: 1.6.0
  - workflowengine: 2.16.0
Disabled:
  - app_api: 34.0.0 (installed 5.0.2)
  - circles: 34.0.0 (installed 27.0.1)
  - contactsinteraction: 1.15.0 (installed 1.13.1)
  - federation: 1.24.0 (installed 1.21.0)
  - privacy: 6.0.0-dev.1 (installed 3.0.0)
  - recommendations: 7.0.0 (installed 1.6.0)
  - related_resources: 5.0.0-dev.0 (installed 2.0.0)
  - support: 6.0.0 (installed 1.11.1)
  - survey_client: 6.0.0-dev.0 (installed 6.0.0-dev.0)
  - systemtags: 1.24.0 (installed 1.21.1)
  - user_ldap: 1.25.0 (installed 1.19.0)

Tips for increasing the likelihood of a response

Use the preformatted text formatting option in the editor for all log entries and configuration output.
If screenshots are useful, feel free to include them.
- If possible, also include key error output in text form so it can be searched for.
Try to edit log output only minimally (if at all) so that it can be ran through analyzers / formatters by those trying to help you.

scubamuc · August 24, 2026, 9:49am

Hey @Cisco30 welcome back

github.com/nextcloud/server

[Bug]: SQLSTATE 1052 "Column 'file_id' in WHERE is ambiguous" in PreviewMapper::getPreviewForSpecification

opened 07:15PM - 13 Aug 26 UTC

closed 07:15AM - 18 Aug 26 UTC

kaynemo

bug 2. developing medium feature: previews and thumbnails 34-feedback

### ⚠️ This issue respects the following points: ⚠️ - [x] This is a **bug**, no…t a question or a configuration/webserver/proxy issue. - [x] This issue is **not** already reported on [Github](https://github.com/nextcloud/server/issues?q=is%3Aopen+is%3Aissue+label%3Abug) OR [Nextcloud Community Forum](https://help.nextcloud.com/) _(I've searched it)_. - [x] Nextcloud Server **is** up to date. See [Maintenance and Release Schedule](https://github.com/nextcloud/server/wiki/Maintenance-and-Release-Schedule) for supported versions. - [x] I agree to follow Nextcloud's [Code of Conduct](https://nextcloud.com/contribute/code-of-conduct/). ### Bug description Preview generation fails on MySQL/MariaDB with: ``` SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous ``` The error is thrown from `OC\Preview\Db\PreviewMapper::getPreviewForSpecification()` every time a preview is saved (`Generator::savePreview()`). In my case it surfaces via the Preview Generator app background job (`OCA\PreviewGenerator\BackgroundJob\PreviewJob`), but the affected code is in **server core**, so on-the-fly preview generation is affected as well. ### Root cause analysis `PreviewMapper::joinLocation()` joins three tables: - `previews` (alias `p`) - `preview_locations` (alias `l`) - `preview_versions` (alias `v`) Both `previews` (`p`) and `preview_versions` (`v`) contain a `file_id` column. `getPreviewForSpecification()` builds WHERE conditions from parameter keys **without a table alias**: ```php public function getPreviewForSpecification(array $parameters): ?Preview { $qb = $this->db->getQueryBuilder(); $this->joinLocation($qb); foreach ($parameters as $key => $value) { $qb->andWhere($qb->expr()->eq($key, $qb->createNamedParameter($value))); } ... } ``` When `$parameters` contains `file_id`, MySQL/MariaDB rejects the query with error 1052 because the column reference is ambiguous. The same problem exists in `getByFileId()`: ```php public function getByFileId(int $fileId): \Generator { $selectQb = $this->db->getQueryBuilder(); $this->joinLocation($selectQb) ->where($selectQb->expr()->eq('file_id', $selectQb->createNamedParameter($fileId, IQueryBuilder::PARAM_INT))); ... } ``` Note that the neighboring method `getAvailablePreviewsForFile()` does it correctly (`'p.file_id'`), so this looks like an oversight. ### Suggested fix Prefix the columns with the proper table alias, e.g.: ```php foreach ($parameters as $key => $value) { $alias = ($key === 'version') ? 'v.' : 'p.'; $qb->andWhere($qb->expr()->eq($alias . $key, $qb->createNamedParameter($value))); } ``` and in `getByFileId()`: ```php ->where($selectQb->expr()->eq('p.file_id', $selectQb->createNamedParameter($fileId, IQueryBuilder::PARAM_INT))); ``` I have applied this patch locally and can confirm the error disappears and previews are generated correctly. ### Steps to reproduce 1. Run Nextcloud 34.0.3/34.0.4 on MySQL or MariaDB. 2. Upload any image file (or install the Preview Generator app and wait for the background job / run `occ preview:generate-all`). 3. Preview generation triggers `Generator::savePreview()` → `PreviewMapper::getPreviewForSpecification()` and fails with SQL error 1052; check `nextcloud.log`. ### Expected behavior Previews are generated and stored without SQL errors. ### Nextcloud Server version 34 ### 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? Updated from a MINOR version (ex. 32.0.1 to 32.0.2) ### Are you using the Nextcloud Server Encryption module? None ### What user-backends are you using? - [x] Default user-backend _(database)_ - [ ] LDAP/ Active Directory - [ ] SSO - SAML - [ ] Other ### Configuration report ```json { "system": { "serverid": "1", "instanceid": "***REMOVED SENSITIVE VALUE***", "passwordsalt": "***REMOVED SENSITIVE VALUE***", "secret": "***REMOVED SENSITIVE VALUE***", "allow_local_remote_servers": true, "trusted_domains": [ "//example.com", "//example.com", "localhost", "//example.com", "localhost", "//example.com" ], "trusted_proxies": "***REMOVED SENSITIVE VALUE***", "push_server_url": "https:\//example.com/push", "datadirectory": "***REMOVED SENSITIVE VALUE***", "dbtype": "mysql", "version": "34.0.3.2", "overwrite.cli.url": "https://example.com", "dbname": "***REMOVED SENSITIVE VALUE***", "dbhost": "***REMOVED SENSITIVE VALUE***", "dbport": "", "dbtableprefix": "oc_", "mysql.utf8mb4": true, "dbuser": "***REMOVED SENSITIVE VALUE***", "dbpassword": "***REMOVED SENSITIVE VALUE***", "installed": true, "maintenance": false, "memcache.local": "\\OC\\Memcache\\APCu", "memcache.distributed": "\\OC\\Memcache\\Redis", "redis": { "host": "***REMOVED SENSITIVE VALUE***", "port": 6379 }, "memcache.locking": "\\OC\\Memcache\\Redis", "theme": "", "loglevel": 2, "overwriteprotocol": "https", "mail_smtpmode": "smtp", "mail_sendmailmode": "smtp", "mail_from_address": "***REMOVED SENSITIVE VALUE***", "mail_domain": "***REMOVED SENSITIVE VALUE***", "mail_smtphost": "***REMOVED SENSITIVE VALUE***", "mail_smtpport": "587", "default_locale": "ru_RU", "default_phone_region": "RU", "app_install_overwrite": { "0": "documentserver_community", "2": "files_rightclick", "3": "metadata", "4": "files_archive" }, "enable_previews": true, "preview_libreoffice_path": "\/usr\/bin\/libreoffice", "enabledPreviewProviders": [ "OC\\Preview\\TXT", "OC\\Preview\\MarkDown", "OC\\Preview\\OpenDocument", "OC\\Preview\\PDF", "OC\\Preview\\MSOffice2003", "OC\\Preview\\MSOfficeDoc", "OC\\Preview\\MSOffice2007", "OC\\Preview\\Image", "OC\\Preview\\Photoshop", "OC\\Preview\\TIFF", "OC\\Preview\\SVG", "OC\\Preview\\Font", "OC\\Preview\\MP3", "OC\\Preview\\Movie", "OC\\Preview\\MKV", "OC\\Preview\\MP4", "OC\\Preview\\AVI" ], "apps_paths": [ { "path": "\/var\/www\/html\/nextcloud\/apps", "url": "\/apps", "writable": false }, { "path": "\/var\/www\/html\/nextcloud\/custom_apps", "url": "\/custom_apps", "writable": true } ], "mail_smtpauth": true, "mail_smtpname": "***REMOVED SENSITIVE VALUE***", "mail_smtppassword": "***REMOVED SENSITIVE VALUE***", "maintenance_window_start": 22, "collabora\/code": "https:\//example.com", "fileuploadnew.chunk_size": "1G", "fileuploadnew.max_filesize": "25G", "memory_limit": "26G", "timeout": 36000, "enable_push": true, "has_internet_connection": true, "notify_push_base_endpoint": "https://example.com\/push", "overwritewebroot": "", "mail_smtpauthtype": "LOGIN", "mail_smtpstreamoptions": { "ssl": { "allow_self_signed": false, "verify_peer": true, "verify_peer_name": true } }, "logtimezone": "Europe\/Moscow", "mail_smtptimeout": 60 } } ``` ### List of activated Apps ```shell Enabled: - activity: 7.0.0 - admin_audit: 1.24.0 - admincockpit: 1.3.4 - analytics: 6.7.1 - announcementbanner: 2.4.3 - appstore: 1.0.0 - bruteforcesettings: 7.0.0 - calendar: 6.5.3 - cloud_federation_api: 1.18.0 - comments: 1.24.0 - contacts: 8.7.6 - contactsinteraction: 1.15.0 - dashboard: 7.14.0 - dav: 1.40.0 - deck: 1.18.3 - external: 9.0.1 - federatedfilesharing: 1.24.0 - federation: 1.24.0 - files: 2.6.0 - files_accesscontrol: 5.0.0 - files_automatedtagging: 5.0.0 - files_downloadlimit: 5.2.0 - files_external: 1.26.0 - files_lock: 34.0.1 - files_pdfviewer: 7.0.0-dev.0 - files_reminders: 1.7.0 - files_retention: 5.0.0 - files_sharing: 1.26.0 - files_trashbin: 1.24.0 - files_versions: 1.27.0 - flow_notifications: 5.0.0 - forms: 5.3.5 - guests: 4.9.0 - localpdf: 1.0.0 - logcleaner: 1.5.6 - logreader: 7.0.0 - lookup_server_connector: 1.22.0 - nextcloud_announcements: 6.0.0 - notes: 6.0.1 - notifications: 7.0.0-dev.1 - notify_push: 1.4.0 - oauth2: 1.22.0 - office: 1.0.0 - onlyoffice: 10.1.2 - password_policy: 6.0.0-dev.0 - previewgenerator: 5.14.0 - privacy: 6.0.0-dev.1 - profile: 1.3.0 - provisioning_api: 1.24.0 - recommendations: 7.0.0 - related_resources: 5.0.0-dev.0 - serverinfo: 6.0.0 - settings: 1.17.0 - sharebymail: 1.24.0 - spreed: 24.0.4 - support: 6.0.0 - survey_client: 6.0.0-dev.0 - systemtags: 1.24.0 - tables: 2.2.1 - tasks: 0.18.1 - text: 8.0.0 - theming: 2.9.0 - thesearchpage: 2.4.3 - twofactor_backupcodes: 1.23.0 - twofactor_totp: 16.0.0 - updatenotification: 1.24.0 - user_status: 1.14.0 - viewer: 7.0.0-dev.0 - weather_status: 1.14.0 - webhook_listeners: 1.6.0 - workflow_script: 5.0.0 - workflowengine: 2.16.0 Disabled: - app_api: 34.0.0 (installed 32.0.0) - circles: 34.0.0 (installed 28.0.0) - encryption: 2.22.0 - files_archive: 1.2.8 (installed 1.2.8) - files_zip: 3.0.0 (installed 3.0.0) - firstrunwizard: 7.0.0-dev.0 (installed 2.18.0) - metadata: 0.24.0 (installed 0.24.0) - photos: 7.0.0 (installed 2.4.0) - side_menu: 6.0.1 (installed 6.0.1) - socialsharing_email: 4.1.0 (installed 4.1.0) - socialsharing_telegram: 4.1.0 (installed 4.1.0) - suspicious_login: 12.0.0-dev.0 - testing: 1.23.0 - twofactor_nextcloud_notification: 8.0.0 - user_ldap: 1.25.0 ``` ### Nextcloud Signing status ```shell ``` ### Nextcloud Logs ```json <details> { "reqId": "Nrd5F8ZlSxmeEMhpV3fM", "level": 3, "time": "2026-08-13T21:35:04+03:00", "app": "core", "message": "Error while running background job OCA\\PreviewGenerator\\BackgroundJob\\PreviewJob (id: 16785, arguments: null)", "version": "34.0.3.2", "exception": { "Exception": "OC\\DB\\Exceptions\\DbalException", "Message": "An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous", "Code": 1052, "Trace": [ { "file": ".../lib/private/Preview/Db/PreviewMapper.php", "line": 250, "function": "findEntity", "class": "OCP\\AppFramework\\Db\\QBMapper" }, { "file": ".../lib/private/Preview/Generator.php", "line": 605, "function": "getPreviewForSpecification", "class": "OC\\Preview\\Db\\PreviewMapper" }, { "file": ".../lib/private/Preview/Generator.php", "line": 566, "function": "savePreview", "class": "OC\\Preview\\Generator" }, { "file": ".../lib/private/Preview/Generator.php", "line": 184, "function": "generatePreview", "class": "OC\\Preview\\Generator" }, { "file": ".../lib/private/PreviewManager.php", "line": 203, "function": "generatePreviews", "class": "OC\\Preview\\Generator" }, { "file": ".../apps/previewgenerator/lib/Service/PreGenerateService.php", "line": 160, "function": "generatePreviews", "class": "OC\\PreviewManager" } ], "Previous": { "Exception": "Doctrine\\DBAL\\Exception\\NonUniqueFieldNameException", "Message": "An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'file_id' in WHERE is ambiguous", "Code": 1052 } } } </details> ``` ### Additional info The bug does not reproduce on PostgreSQL/SQLite in the same way only if those engines resolve the ambiguity differently; on MySQL/MariaDB it fails consistently on every preview save. Happy to submit a PR with the fix above if maintainers agree with the approach.

feel free to add your heads-up

Cisco30 · August 24, 2026, 12:43pm

Thanks for the information; I am tracking the issue on GitHub now. I will close the topic once it is resolved on GitHub.