Freeradius and check connection to DB

[vanish]

Thanks for your answer.
Install freeradius 3.0.12 and iODBC.
Read docs at http://networkradius.com/doc/3.0.10
Can't understand - how work multiple sql instances in v3?
In freeradius v2 it works clear for me:

- Create in sql.conf:

  sql sql_instance1 {
        ...
  }
  sql sql_instance2 {
        ...
  }

- Use:

On virtual server1:

  authorize {
        sql_instance1
  }

  accounting {
        sql_instance1
  }

On virtual server2:

  authorize {
        sql_instance2
  }

  accounting {
        sql_instance2
  }

But in 3-d version i can't understand how it works.
Where i can find more detail info about this in v3 with examples?