Gnucash 2.3.0 - Database schema and third party tools

[marcus.wolschon at googlemail.com]

Hello,

is there some documentation on the database-schema
Gnucash 2.3 introduces, the foreign keys used, if
transactions are used, where future extensions are
supposed to be added,...?
I'd like to give it a close look to see how much
I need to change any of my existing database-backend
of jGnucashLib to handle gnucash's own new scheme.

(I hope there is still support for slots. They have
 proven quite useful to store additional information
 that is ignored by gnucash.
 Such as references to receipts in a document-management-
 system or computer-readable references of a transaction
 to a webshop-order, paypal-transaction, ebay-sale, ...it
 was automatically generated from to be used by
 specialized plugins/batches/statistics/viewers.)

On http://gnucash.org/docs.phtml I see documentation
for users and documentation-writers but nothing
for developers yet.

As it's a database now... is anyone working on a web-
based viewer or even minimal editor? I envision a lot
of useful integrations with other software here as
anything in a small business ultimately has a trail
in the book-keeping. At least a viewer should be easy
to do. I remember I even have some incomplete GWT-based
and a php-based viewer lying around somewhere that I
wrote as a test.

Marcus