slapd 2.0.23, sizelimit and clever filter refining

[Andreas Schuldei <andreas@schuldei.org>]

In debian woody there is slapd 2.0.23, which i am using in the
skolelinux project. 

when getting a list of all posix groups we surpass the default
limit of 500, since there are the user-private groups (every user
has its own group) plus all the classes and groups, which are
also posix groups. And then there might be some admin setting the
SIZELIMIT to something even smaller, to increase performance.

I am now looking for a way to work around this SIZELIMIT in a
clean way, without relying on some special setting in the
configuration file.

i would like to to do this:
get_section 
  if (sizelimit exceeded) 
    split up section 
    foreach section  
      get_section 
    end 
  end 
end 

the query should be split up recursivly untill i retrived all the
data without hitting the sizelimit. i thought the splitting up of
the query could happen most elegantly by refining the filtering
more and more. 

I am sure some clever mind allready solved this problem since it
surely occured before. I would like to adapt copy/paste the
solution. (c:

thanks in advance!

Andreas