=== Error ===
Request URL: (Special:MovePage)
Request ID: `XNnkVApAICwAAK-hLCQAAAAH`
```name=message
Wikimedia\Rdbms\DBQueryError from line 1587 of /srv/mediawiki/php-1.34.0-wmf.4/includes/libs/rdbms/database/Database.php: A database query error has occurred.
…
Query: UPDATE `page` SET page_namespace = '0',page_title = 'Dymitr_(Bekiaris-Mawrogonatos)' WHERE page_id = '4538506'
Function: MovePage::moveToInternal
Error: 1062 Duplicate entry '0-Dymitr_(Bekiaris-Mawrogonatos)' for key 'name_title' (10.64.0.110)
```
```name=trace,lines=10
…
#3 /srv/mediawiki/php-1.34.0-wmf.4/includes/MovePage.php(620): Wikimedia\Rdbms\Database->update(string, array, array, string)
#4 /srv/mediawiki/php-1.34.0-wmf.4/includes/MovePage.php(318): MovePage->moveToInternal(User, Title, string, boolean, array)
#5 /srv/mediawiki/php-1.34.0-wmf.4/includes/MovePage.php(286): MovePage->moveUnsafe(User, string, boolean, array)
#6 /srv/mediawiki/php-1.34.0-wmf.4/includes/specials/SpecialMovepage.php(597): MovePage->moveIfAllowed(User, string, boolean)
#7 /srv/mediawiki/php-1.34.0-wmf.4/includes/specials/SpecialMovepage.php(128): MovePageForm->doSubmit()
#8 /srv/mediawiki/php-1.34.0-wmf.4/includes/specialpage/SpecialPage.php(569): MovePageForm->execute(NULL)
#9 /srv/mediawiki/php-1.34.0-wmf.4/includes/specialpage/SpecialPageFactory.php(575): SpecialPage->run(NULL)
#10 /srv/mediawiki/php-1.34.0-wmf.4/includes/MediaWiki.php(288): MediaWiki\Special\SpecialPageFactory->executePath(Title, RequestContext)
#11 /srv/mediawiki/php-1.34.0-wmf.4/includes/MediaWiki.php(865): MediaWiki->performRequest()
#12 /srv/mediawiki/php-1.34.0-wmf.4/includes/MediaWiki.php(515): MediaWiki->main()
#13 /srv/mediawiki/php-1.34.0-wmf.4/index.php
```
=== Impact ===
User are trying to move a page or change its title, and some of the time, this action is failing.
They are shown a generic "Internal error" page with no further information about what is wrong or what to do.
=== Notes ===
This exact trace was from user web request, and seen at least 6 different times in Logstash (past few weeks). Affects en.wikipedia.org, commons.wikimedia.org, pl.wikipedia.org, and ru.wikipedia.org, and possibly others.
The following two are found from the same code path and significantly more prominent, from job runners and api requests.
>>! **Related 1 (Deadlock found) / server: job runners**
> From CentralAuth/LocalRenameJob.
> Seen 111 times in last few weeks.
> Affects commonswiki, dewiki, …
>
> ```name=trace
> Query: UPDATE `page` SET page_namespace = '2',page_title = '<a user name>/<a user sub page>' WHERE page_id = '<a page id>'
> Function: MovePage::moveToInternal
> Error: 1213 Deadlock found when trying to get lock; try restarting transaction
>
> #2 /srv/mediawiki/php-1.34.0-wmf.1/includes/libs/rdbms/database/Database.php(2195): Wikimedia\Rdbms\Database->query(string, string)
> #3 /srv/mediawiki/php-1.34.0-wmf.1/includes/MovePage.php(565): Wikimedia\Rdbms\Database->update(string, array, array, string)
> #4 /srv/mediawiki/php-1.34.0-wmf.1/includes/MovePage.php(263): MovePage->moveToInternal(User, Title, string, boolean, array)
> #5 /srv/mediawiki/php-1.34.0-wmf.1/extensions/CentralAuth/includes/LocalRenameJob/LocalPageMoveJob.php(73): MovePage->move(User, string, boolean)
> #6 /srv/mediawiki/php-1.34.0-wmf.1/extensions/CentralAuth/includes/LocalRenameJob/LocalPageMoveJob.php(55): LocalPageMoveJob->movePage(Title, Title)
> #7 /srv/mediawiki/php-1.34.0-wmf.1/extensions/EventBus/includes/JobExecutor.php
> ```
>>! **Related 2 (Lock wait timeout exceeded) / server: api requests
> From action=move API (ApiMove)
> Seen 29 times in last few weeks
> Affects commonswiki, dewiki, euwiki, ruwiki, …
>
> ```name=trace
> #2 /srv/mediawiki/php-1.34.0-wmf.1/includes/libs/rdbms/database/Database.php(2195): Wikimedia\Rdbms\Database->query(string, string)
> #3 /srv/mediawiki/php-1.34.0-wmf.1/includes/MovePage.php(564): Wikimedia\Rdbms\Database->update(string, array, array, string)
> #4 /srv/mediawiki/php-1.34.0-wmf.1/includes/MovePage.php(263): MovePage->moveToInternal(User, Title, string, boolean, array)
> #5 /srv/mediawiki/php-1.34.0-wmf.1/includes/api/ApiMove.php(190): MovePage->move(User, string, boolean, array)
> #6 /srv/mediawiki/php-1.34.0-wmf.1/includes/api/ApiMove.php(87): ApiMove->movePage(Title, Title, string, boolean, array)
> #7 /srv/mediawiki/php-1.34.0-wmf.1/includes/api/ApiMain.php(1593): ApiMove->execute()
> #8 /srv/mediawiki/php-1.34.0-wmf.1/includes/api/ApiMain.php(531): ApiMain->executeAction()
> #9 /srv/mediawiki/php-1.34.0-wmf.1/includes/api/ApiMain.php(502): ApiMain->executeActionWithErrorHandling()
> #10 /srv/mediawiki/php-1.34.0-wmf.1/api.php
> ```