Question: what's the benifit of compile in database support?

[FKtPp]

Dear developers,

As the subject said I have a stupid question, what is the advantages
of compile in a database support like:

--8<---------------cut here---------------start------------->8---
Databases:
  Compiling in support for Berkeley database.
--8<---------------cut here---------------end--------------->8---

Can I use this in elisp scripts inside XEmacs, If so, how to use it? 
Is there any documents/info pages describe this kind of usage?

-- 
ENCODING