At the moment I have only really thought about Postgres Suport.
There are to reasons for this:

1. I like it
2. I have it

I am interested in adding extra support for different SQL systems.
Hopefully mySQL will be added in the next release with other
datebases to follow. 


Postgres Set-up


1. The username for the database at the moment is set to vfs. You can 
change this by editing the top of db_wrapper.inc

2. You will have to create the vfs database and connect to it as the
vfs user using psql. You can then run \i vfs.sql and it will load
the database schema.


NOTE
====

Currently this system uses blobs (Binary Large Objects) to store
the files into the database. Postgres will only allow a superuser
to store blobs so you therefore have to make sure that the vfs user
has sufficient priviledges.