I submitted a post about something similar two weeks ago:
wordpress.org/support/topic/sql-database-infected-or-just-bloated
Found possible problems in Option _transient_feed_895a6fef0cc57461ead214388fd67e81 (script tag )
Just to take an example, "Yoast" appears 35 times alone in this 14KB excerpt (total size is 218KB). I once had Yoast's SEO plugin installed, deleted long ago.
Who else but Yoast himself would inject and bloat the database with "Yoast"? This could seem to suggest foul play. Does anyone have another explanation?
[excessive code deleted]