MyISAM I assume? InnoDB, which I hope you're using, uses MVCC too, just like pretty much all mainstream SQL databases of the last 30 years. Updates occur in pla

MyISAM I assume? InnoDB, which I hope you're using, uses MVCC too, just like pretty much all mainstream SQL databases of the last 30 years. Updates occur in place, with the older version of the columns relocated to UNDO space. Not sure what you're gaining over PostgreSQL there. Also, if the column is indexed, the index will contain all versions for each row. This is what allows index scans.