For my project, www.wikigaming.com, I am eventually going to break it into two or more mediawiki installs but I would like a user to only have to sign up on one site and have an account on all the others. I don't have root access to the host or any way to run a LDAP server, so I can't do something like that, and I would prefer to not have to change the code if at all possible (or at least in a minimal way).

I have an elegant solution for a postgreSQL (or mysql 5) install, but unfortunately, postgre support is still experimental (and my host does not have pg dbs). It goes like this: 1) Remove the user table from all databases. 2) Either create a new database (lets call it main) or designate an existing database to be the main one. 3) Create the user table on the main db. 4) Create views on all other dbs that shadows the main.user table. This should, unless I'm missing something, work seamlessly. watchlist and user_rights would still stay project-dependent... or you could shadow user_rights in the same way if you want an admin on one project to be an admin on all projects. Any comments on if this would work as planned?

I have also thought about a much less elegant solution for MySQL which would basically use a brute force method with triggers to update all user tables whenever one user table changes. With a lot of users, I could see this being a major performance hit, though. Any ideas how else this could be done in MySQL?

Finally, has anyone written any code to do this very same thing?