Re: How can I look at a recursive table dependency tree?

On Mon, 19 Jan 2009 14:41:12 +0000
Richard Huxton <dev@archonet.com> wrote:

> Ivan Sergio Borgonovo wrote:
> > On Mon, 19 Jan 2009 14:19:51 +0000
> > Richard Huxton <dev@archonet.com> wrote:
> >
> >> Igor Katson wrote:
> >>> Is there a way to watch all dependencies recursively without
> >>> doing a drop?
> >
> >> BEGIN;
> >> DROP CASCADE...
> >> -- check things
> >> ROLLBACK;
> >
> > Isn't it going to be a pretty expensive way to see?

> Not necessarily - you're not likely to have a lot of concurrency
> on a backup database. And we are all testing this sort of stuff on
> a backup database, aren't we?

Isn't it going to be expensive even if there is no concurrency?

mvcc should be pretty efficient to rollback transactions but... well
it should have a cost anyway... and you add deleting to rolling
back, not just traversing some schema somehow.

Surely recursively traversing a schema may be expensive in termos of
programming time if there is no pre-build function.

--
Ivan Sergio Borgonovo
http://www.webthatworks.it