Subject Foreign keys like index
Author Sasa Mihajlovic

I have a little newbie question for Firebird masters.
If I have 2 tables (for example) orders and customers where orders
are "slave" table for customers with foreign key on it.

if I write statement like this:

select,, o.orderno, o.orderdate
from orders o
join cutomers c on = o.cutd_id
order by

does firebird use foreign key like index