Indexes on foreign keys
SQL Server automatically creates a clustered index on a primary key column/s.
You can change this to be a non clustered index if required, maybe there is a better choice for the clustered index.
When you create a foreign key, nothing happens except the building of the PK/FK relationship.
Should creating a FK also create a non clustered index. I think that it should.
This could help query performance, especially joins.