Hi again
I got to thinking that doing a tree address like this, the parent address
is all but the last dot-number of the current address, so is redundant,
as it can be derived from the current address.
So, the new idea looks something like this:
CREATE TABLE categories ( category char(30) NOT NULL, cat_id char(255) PRIMARY KEY, nidsufix
int4 DEFAULT 1 NOT NULL, UNIQUE ( category, substr(cat_id, 1, lenght(cat_id) - (lenght(cat_id) -
strpos(cat_id,'.')))));
Two problems
1. functions can not be called from inside of the UNIQUE constraint?
2. strpos() returns the FIRST '.', and I need the LAST '.'. Is there a
similar function that will return the last position of the substring?
If both of these can not be resolved, then it will be neccesary to use a
parent id field, even though that infomation is contained with in the
cat_id field.
Thanks
Terry Mackintosh <terry@terrym.com> http://www.terrym.com
sysadmin/owner Please! No MIME encoded or HTML mail, unless needed.
Proudly powered by R H Linux 4.2, Apache 1.3, PHP 3, PostgreSQL 6.4
-------------------------------------------------------------------
Success Is A Choice ... book by Rick Patino, get it, read it!