LDAP operations questions

[Weston Bustraan <weston@itdonline.net>]

I have a couple of questions concerning data in LDAP directories and
searching.

1. Is it possible to have LDAP force an attribute to be unique? Similar to
the way it is done in SQL? The reason I ask, is that I would like to
ensure every user entry in the directory has a unique uidNumber. It could
be a security problem if someone acceidentally sets two users to have the
same uidNumber.

2. Is there a way to get the maximum value of an attribute during a
search? I have a bunch of users in the directory and I would like to
a) find out what the next uidNumber is, and b) find out what IP addresses
have been assigned users and which ones are free.