Ahh, thanks for this!
On Tue, Aug 25, 2015 at 5:47 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> rmcgehee(at)gmail(dot)com writes:
> > The lag() window function is documented to accept a default argument.
> > However, if lag is applied to either a float or a real (and possibly
> other
> > types as well), adding a default gives an error.
>
> The default argument has to be the same type as the value argument;
> in your failing example, it is not. Perhaps the documentation could be
> more explicit about that.
>
> regards, tom lane
>