On Thu, Dec 17, 2015 at 9:13 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
Whether we really need a feature like that isn't clear though; it's not like it's hard to test things that way now. Stick in a BEGIN with no COMMIT, you're there. The problem only comes in if you start expecting the behavior to be bulletproof. Maybe I'm being too pessimistic about what people would believe a --dry-run switch to be good for ... but I doubt it.
I'm on the same line: BEGIN/ROLLBACK requires trivial effort and a --dry-run option might give a false sense of security, but it cannot possibly rollback side-effects of user functions which modify filesystem or interact with the outside world in some other way.