tree structure photo gallery date quiery

Hi folks.

I'm looking at the possibility of implementing a photo gallery for my
web site with a tree structure, something like:

create table gallery (
id serial,
parent int4,
name varchar(40),
primary key (id));

create table photos (
pid serial,
id int4 references gallery not null,
added timestamp,
pfile varchar(128) not null,
pdesc varchar(40) not null,
primary key (pid));

copy "gallery" from stdin;
1 0 Root
2 1 NYMR
3 1 Middleton
4 2 Steam Gala
5 2 Diesel Gala
6 2 From The Footplate
7 3 From The Footplate
\.

copy "photos" from stdin;
1 4 2004-11-10 10:10:00 80135-1.jpg 80135 light-engine
2 4 2004-11-10 12:12:00 6619-1.jpg 6619 on-shed
3 5 2004-10-01 10:00:00 D7628.jpg Sybilla
4 7 2004-01-01 09:12:12 mm-21.jpg No. 4 Mathew Murrey
\.

How would I go about creating a view to show a) the number of photos in
a gallery and b) the timestamp of the most recent addition for a
gallery, so that it interrogates all sub-galleries?

For example NYMR should return 3, 2004-11-10 12:12, Middleton should
return 1, 2004-01-01 09:12:12 and Root should return 4, 2004-11-10
12:12:00
--
Gary Stainburn

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