Sharding a huge database index (or other binary tree structure) onto 7 different servers or hard drives? Or 49 (recursively apply it)? I don't know if that's ac

Sharding a huge database index (or other binary tree structure) onto 7 different servers or hard drives? Or 49 (recursively apply it)? I don't know if that's actually useful here but it's the first thing that came to mind.