On the page: http://331531hw.shoutwiki.com/w/index.php?title=Odev2
When clicked on the Save changes button, a blank page is displayed (and the page is not saved), when clicked on the show preview button the errors below are displayed:
Backtrace:
#0 /var/www/live/w/includes/libs/rdbms/database/Database.php(1476): Wikimedia\Rdbms\Database->makeQueryException(string, integer, string, string)
#1 /var/www/live/w/includes/libs/rdbms/database/Database.php(1236): Wikimedia\Rdbms\Database->reportQueryError(string, integer, string, string, boolean)
#2 /var/www/live/w/includes/libs/rdbms/database/Database.php(1703): Wikimedia\Rdbms\Database->query(string, string)
#3 /var/www/live/w/includes/libs/rdbms/database/Database.php(1794): Wikimedia\Rdbms\Database->select(string, array, array, string, array, array)
#4 /var/www/live/w/extensions/Math/src/MathRenderer.php(275): Wikimedia\Rdbms\Database->selectRow(string, array, array, string)
#5 /var/www/live/w/extensions/Math/src/MathRenderer.php(596): MathRenderer->readFromDatabase()
#6 /var/www/live/w/extensions/Math/src/MathHooks.php(224): MathRenderer->checkTeX()
#7 /var/www/live/w/extensions/Math/src/MathHooks.php(211): MathHooks::mathPostTagHook(MathPng, Parser)
#8 /var/www/live/w/includes/parser/Parser.php(3968): MathHooks::mathTagHook(string, array, Parser, PPFrame_DOM)
#9 /var/www/live/w/includes/parser/Preprocessor_DOM.php(1364): Parser->extensionSubstitution(array, PPFrame_DOM)
#10 /var/www/live/w/includes/parser/Parser.php(3014): PPFrame_DOM->expand(DOMElement, integer)
#11 /var/www/live/w/includes/parser/Parser.php(1350): Parser->replaceVariables(string)
#12 /var/www/live/w/includes/parser/Parser.php(476): Parser->internalParse(string)
#13 /var/www/live/w/includes/content/WikitextContent.php(341): Parser->parse(string, Title, ParserOptions, boolean, boolean, NULL)
#14 /var/www/live/w/includes/content/AbstractContent.php(517): WikitextContent->fillParserOutput(Title, NULL, ParserOptions, boolean, ParserOutput)
#15 /var/www/live/w/includes/EditPage.php(4048): AbstractContent->getParserOutput(Title, NULL, ParserOptions)
#16 /var/www/live/w/includes/EditPage.php(3962): EditPage->doPreviewParse(WikitextContent)
#17 /var/www/live/w/includes/EditPage.php(2749): EditPage->getPreviewText()
#18 /var/www/live/w/includes/EditPage.php(702): EditPage->showEditForm()
#19 /var/www/live/w/includes/actions/EditAction.php(60): EditPage->edit()
#20 /var/www/live/w/includes/actions/SubmitAction.php(38): EditAction->show()
#21 /var/www/live/w/includes/MediaWiki.php(501): SubmitAction->show()
#22 /var/www/live/w/includes/MediaWiki.php(294): MediaWiki->performAction(Article, Title)
#23 /var/www/live/w/includes/MediaWiki.php(860): MediaWiki->performRequest()
#24 /var/www/live/w/includes/MediaWiki.php(517): MediaWiki->main()
#25 /var/www/live/w/index.php(42): MediaWiki->run()
#26 {main}