How to locate user tables in another database for multisite-single-login

1. I am developing multi-sites with drupal.

   1. I have to take care of 10 sites and they need single login

   2. I supposed I need to create separate user database to support that feature.

   3. i.e 10 sites, 10 database and +1 user database.

   4. Where should I look and modify? U开发者_JS百科ser Module? Which lines?

   5. Normally database settings are in settings.php file .

   6. I had export the database and make and working user-database already.

Please kindly try to explain in details thanks.

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I don't know the full details of your situation but it sounds like you might benefit from one database with prefixed tables and a shared user table.

See http://thedrupalblog.com/setting-multi-site-drupal-6-installation-shared-databases-and-single-sign and http://drupal.org/node/201673 (bit outdated but may still be helpful)