Aside from moving them into what many would consider an inferior container, do you really need 10 years and a million records in one back end that you'll be querying against from now on? You could split into multiple back ends based on time spans? Record count isn't a good indicator of file size, which is more important.
Your performance problem might be from repeatedly deleting and recreating tables, which is something I wouldn't do. Better to just update and append what you have.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.