You can have the tag history data be logged in two different database providers by downloading and installing the Tag History Splitter module.

To use the tag history splitter

Once the module is installed, to create the additional tag history provider, do the following steps:

Go to the Configure section of the Gateway, and choose Tags>History from the menu on the left.
Go to the bottom of the Database Tag History Providers page, and click Create new Historical Tag Provider.
The Add Historical Tag Provider Step 1: Choose Type page is displayed.
Select Tag History Splitter and click Next.
The New Historical Tag Provider page is displayed.
Enter a name for the Provider Name, and from the dropdown choose a database for the First Connection (for the primary data) and one for the Second Connection (for secondary data).
Click Create New Historical Tag Provider.
Now the splitter tag provider is created and you can use it to log the tag history data in the Designer.
Check this by going back to the Designer, selecting a tag and then right-clicking to select the Edit tags. On the Tag Editor window go to the History tab and see the new splitter provider in the dropdown of the History Provider.

Tag History Splitter