Roberto Mello schrieb:
> Looks like you want something similar to Oracle's CONNECT BY statement.
> There are some solutions to that. At OpenACS we had to deal with that so
> implemented something like what you described here.
> However, the methods described by Joe Celko is his book "SQL For
> Smarties" on chapters 28 and 29 (I think) are better and more robust. If
> you search for "trees" and related topics at the openacs.org and
> arsdigita.com's web/db web bulletin boards, you'll find several hits.
Thanks, the solutions discussed on these sites suggest the use of lookup
tables with parent and child for each record. I have thought about the
same, but thought the arrays in Postgres could provide a more elegant
way of building a tree.
I want to migrate from MySQL to Postgres mainly because the array and
subselect features. And finally the article at
http://www.phpbuilder.com/columns/tim20001112.php3 convinced me it could
run on my small machine. But it appears to me that the arrays always are
handled like strings and are not really useful for anything advanced. I
can't really believe it, please prove me wrong! I have set great hope in
Postgres. :)
Alvar
--
Alvar C.H. Freude | alvar.freude@merz-akademie.de
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