In one of the leagues I'm applying the website we have 3 different leagues running under the same organisation. We would like to have the ratings calculated over all the games played, which requires a more complex database setup. Some of the core tables and some of the league specific tables need to be shared, which can be achieved with MySQL's Views.

1. Choose the “master” site from which the users will be shared (this is the database which will actually store the data).
2. Copy the $secret value from the master site's configuration.php file to the same file on all the “slave” sites.
3. Ensure access to the master site's database is given to the users of each of the slave sites' databases.
4. Run the following commands on each slave site table:

   DROP TABLE ipl_users
   CREATE VIEW ipl_users AS SELECT * FROM master.ipl_users

5. If you need to connect leagues with existing data, you need to adjust IDs in the following tables: xxx
6. You can check whether all primary keys are consecutive with the following SQL query:

   SELECT a.id+1 AS start, MIN(b.id) - 1 AS end
   FROM master AS a, master AS b
   WHERE a.id < b.id
   GROUP BY a.id
   HAVING start < MIN(b.id)

7. List of tables to be shared:

• Make sure to set Session Handler to “none” in Global Configuration → System. The database session handler does not work well with shared tables.

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