On Sat, Jul 27, 2019 at 4:03 PM Bartosz Dziewoński matma.rex@gmail.com wrote:
The 'searchindex' table uses MyISAM because until recently, InnoDB did not support fulltext indexes, which MediaWiki uses for the search. All other tables should use InnoDB.
According to https://stackoverflow.com/a/9397060 fulltext indexes are available on InnoDB since MySQL 5.6.4. If you're running that version or newer, it is possible you could use InnoDB for that table, but as far as I know no one has tried it before.
According to https://www.mediawiki.org/wiki/Compatibility#Database MediaWiki only requires MySQL 5.5.8, so we can't change that in our table definitions (yet).
No idea about the 'math' table.
The math table isn't used, and it is being dropped in production: https://phabricator.wikimedia.org/T196055
Regarding MyISAM vs InnoDB: Always use InnoDB unless you have a very good reason to use MyISAM (like the one mentioned about full-text indexes).
Cheers Manuel.