Re: Window functions can be created with defaults, but they don't work

Robert Haas <robertmhaas@gmail.com> writes:
> On Fri, Aug 30, 2013 at 6:14 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> The reason this crashes is that the planner doesn't apply
>> default-insertion to WindowFunc nodes, only to FuncExprs.

> I'm not sure I agree.  Under that approach, any functions that have
> already been created like that will still crash the server.  A
> malicious user could create a function like this now and wait to
> crontab it until the day he's leaving the company.  Or there are more
> accidental scenarios as well.

The crash is only possible because the underlying internal-language
function doesn't sanity-check its input enough to catch the case of too
few arguments.  As such, it's not that different from hundreds of other
cases where a superuser can cause a crash by misdeclaring the arguments to
an internal-language function.  So I don't find your argument compelling.
I'd even say this was user error, except that it's not obvious that this
case shouldn't work.
        regards, tom lane