Index Limitations with DBs?

["Lon Tierney" <ltierney@mykungfuisthebest.net>]

At the Developer Day - SF, it was mentioned in Howard's talk about
Hierarchical DB backend that BDB can not use indexes if there are over 64K
entries in the DB. I don't recall what that had to do with the topic, but
I am wondering how that applies to the choice of DB implementation?

Is there a DB implementaiton that will give better indexing capabilities
with LARGE numbers of entries? Here I am assuming LDBM backend.

Thanks!
-lon