Indeed. Wouldn't it be a cool feature to persists transaction states across connections so that a new connection could get access to a sub- transaction state? That way, you could make your schema changes and test them with any number of test clients (which designate the state to connect with) and then you would commit when everything works.
Actually you can hack this by starting your webserver with only 1 thread, use persistent connections, and disable all commits in the application.
But I'd call that "a very hackish hack". ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org/