I have a table with more than 60mio records, where every month I have to add about 2-4 milions. It's not insert only table, I need to read from it and update recently added rows (status changes, etc.). I have spotted some of my SELECT queries begun to ommit indexes because of number of rows to be searched using criterias. Therefore I want to archive records older than 6 months. Is there any good way to do this? Only thing I got in mind is manual copying data to archive db and remove at master. Perhaps there are some good practices or mechanisms to do it?