When using Semantic Drilldown extension on a multi-database MediaWiki installation with MySQL 5.7 slave, visiting Special:BrowseData causes the following database error:
A database error has occurred. Did you forget to run maintenance/update.php after upgrading? See: https://www.mediawiki.org/wiki/Manual:Upgrading#Run_the_update_script Query: CREATE TEMPORARY TABLE semantic_drilldown_values ( id INT NOT NULL ) Function: SDBrowseDataPage:createTempTable Error: 1787 Statement violates GTID consistency: CREATE TEMPORARY TABLE and DROP TEMPORARY TABLE can only be executed outside transactional context. These statements are also not allowed in a function or trigger because functions and triggers are also considered to be multi-statement transactions. (geo-db-smw-slave.query.consul)
This is because of restrictions on GTID-based replication in newer versions of MySQL. A workaround is to use auto-commit mode for temporary table operations, as implemented in Semantic MediaWiki itself.