It's not my DB. I don't know anything much about DB design, so I was just using what I was given. I don't see any reason why we sessions and sessions_metadata couldn't be merged though.
I'll give it a go with my local version (might take a while!).

If I do that then I'll have just a sessions table with a FK to users - right?

So Sessions.pm

has_a(username=>'Users')
[download]

and Users

has_many(sessions=>[Sessions=>'username']=>'username)
[download]

Does that sound right?

Cxx