Re: [PERFORM] Nested Sets WAS: column size too large, is this a bug?
Robert, If you search the pgsql-sql archives you'll find some helpful threads on using nested sets in PostgreSQL, one in particular I was involved with was a generic move_tree function that enabled moving a node from one branch to another. I have to admit to failing to follow -SQL over the last few months.This list and Hackers are pretty much the only ones I read all of. Maybe I should get back on -SQL and we can compare move_tree functions :-) Did yours use a temp table, or some other means? -- Josh Berkus Aglio Database Solutions San Francisco ---(end of broadcast)--- TIP 4: Don't 'kill -9' the postmaster
Re: [PERFORM] Nested Sets WAS: column size too large, is this a bug?
On Tuesday 30 March 2004 11:38, Josh Berkus wrote:
Robert,
If you search the pgsql-sql archives you'll find some helpful threads on
using nested sets in PostgreSQL, one in particular I was involved with
was a generic move_tree function that enabled moving a node from one
branch to another.
I have to admit to failing to follow -SQL over the last few months.This
list and Hackers are pretty much the only ones I read all of.
Maybe I should get back on -SQL and we can compare move_tree functions :-)
Did yours use a temp table, or some other means?
Nope, Greg Mullane and I worked out the math and came up with an algorithm of
sorts that we could apply to the tree when moving elements.
digs a little
http://archives.postgresql.org/pgsql-sql/2002-11/msg00355.php
Seemed to work though someone else had posted yet another version after
ours... and in fact the one posted is not exactly what I use now either :-)
Robert Treat
--
Build A Brighter Lamp :: Linux Apache {middleware} PostgreSQL
---(end of broadcast)---
TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]
Re: [PERFORM] Nested Sets WAS: column size too large, is this a bug?
Robert, http://archives.postgresql.org/pgsql-sql/2002-11/msg00355.php Seemed to work though someone else had posted yet another version after ours... and in fact the one posted is not exactly what I use now either :-) Hmmm ... I'd want to do a *lot* of testing before I trusted that approach. Seems like it could be very vunerable to order-of-exection issues. I'll start a GUIDE on it, people can post their various Nested Sets solutions. -- -Josh Berkus Aglio Database Solutions San Francisco ---(end of broadcast)--- TIP 6: Have you searched our list archives? http://archives.postgresql.org
