Adding wikiid field to table online...Wikimedia\Rdbms\DBQueryError from line 1618 of /../includes/libs/rdbms/database/Database.php: Error 1064: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'varchar(255) NOT NULL default '' AFTER `timestamp`' at line 1
Function: Wikimedia\Rdbms\Database::sourceFile( /../extensions/WhosOnline/includes/../sql/patch-add-wikiid-field.sql )
Query: ALTER TABLE `07000_online` ADD COLUMN varchar(255) NOT NULL default '' AFTER `timestamp`
#0 /../includes/libs/rdbms/database/Database.php(1602): Wikimedia\Rdbms\Database->getQueryException()
#1 /../includes/libs/rdbms/database/Database.php(1576): Wikimedia\Rdbms\Database->getQueryExceptionAndLog()
#2 /../includes/libs/rdbms/database/Database.php(952): Wikimedia\Rdbms\Database->reportQueryError()
#3 /../includes/libs/rdbms/database/Database.php(3302): Wikimedia\Rdbms\Database->query()
#4 /../includes/libs/rdbms/database/Database.php(3241): Wikimedia\Rdbms\Database->sourceStream()
#5 /../includes/libs/rdbms/database/DBConnRef.php(103): Wikimedia\Rdbms\Database->sourceFile()
#6 /../includes/libs/rdbms/database/DBConnRef.php(807): Wikimedia\Rdbms\DBConnRef->__call()
#7 /../includes/installer/DatabaseUpdater.php(729): Wikimedia\Rdbms\DBConnRef->sourceFile()
#8 /../includes/installer/DatabaseUpdater.php(802): DatabaseUpdater->applyPatch()
#9 /../includes/installer/DatabaseUpdater.php(547): DatabaseUpdater->addField()
#10 /../includes/installer/DatabaseUpdater.php(515): DatabaseUpdater->runUpdates()
#11 /../maintenance/update.php(209): DatabaseUpdater->doUpdates()
#12 /../maintenance/includes/MaintenanceRunner.php(309): UpdateMediaWiki->execute()
#13 /../maintenance/doMaintenance.php(85): MediaWiki\Maintenance\MaintenanceRunner->run()
#14 /../maintenance/update.php(319): require_once('/var/www/htdocs...')
#15 {main}
This is what I am getting on REL1_39 of the extension. If I move to REL1_40, the issue goes away due to this fix. To cut it short, use REL1_40 for MediaWiki 1.39.x!