>> The simplest way to do it is to construct tables that look just like the
>> b-tree relations used in a custom LDAP data store. However this doesn't
>> goal achieve #2 above.
> Can you explain this more?

Basically he's saying model the db like you do the jdbm tables in the
ldbm rip off we use for the default backing store.

Meaning you have a master table, an id2dn table, and so on just like
using jdbm tables.

If we go to RDBMS, this would be the worst approach. It is suppose to be a relationnal model, not an hierarchical model mapped on a relationnal model. Performance will be awfull