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
