I’m going through to clean up and optimize a large multisite network install and I noticed almost all _micro_revisions tables have data in them but dating back a few years ago, not seeing anything recent.
My questions is it safe to empty the _micro_revisions tables from myphpadmin? Since it is just revision data I would presume it is not being used on the live site, but instead, old data that is being stored in the revision library.
Yes it’s safe to delete – if you don’t expect to make use of any revisions. Revisions are very useful when actively working in Microthemer, in case you want to revert some design changes. But if they are years old your current design has probably ‘settled’.