Application Design and PostgreSQL

Hi,

i asked some question about this topic few weeks ago, but i am still
thinking about good application design with postgresql.

good apps have three components:

- frontend (like html, gui, psql etc.)
- middleware (Objectorientated modules)
- backend (postgresql)

But then i thought: Do i really need complex middleware or is it just
a wrapper around PostgreSQL??

I think its possible to implement the whole logic inside postgresql.

You always have some persistent objects and some non-persistent
objects. and persistent objects may have some attributes which are
not-persistant.

now i build classes inside postgresql.

persistents objects => tables
non-persistent obj. => views
and so on
and i also can implement all object methods inside postgresql

like init() methods inside an object are triggers inside postgresql.

if i add a new object to database i can implement a function which
accepts the new data and checks it, so i can also do the error
checking in postgresql.

i still have big problems with thinking about this stuff.
I already wrote some oo-apps and i am familiar with it. but i always
took a home-brew solution for object persistence. In these
applications the whole logic was programmed inside the oo-modules.

i am still looking for a real world example like a cd database which
has an object orientaded interface and storing persistent objects in
postgres. and all book just describe SQL _OR_ OO-Programming.

Anybody here who likes to keep my brain burning?? Can anybody show me
a small app with oo design and postgfresql persistence? Any hints for
further readings or books? anybody who has the same problems and
wants to discuss those things.

janning

--
Planwerk 6 /websolutions
Herzogstraße 86
40215 Düsseldorf

fon 0211-6015919
fax 0211-6015917
http://www.planwerk6.de