Re: Confusing order by error

> --- david.g.johnston@gmail.com wrote:
>
> On Fri, Mar 31, 2017 at 2:45 PM, <kbrannen@pwhome.com> wrote:
>
> > I can go with that now that I understand it (and I did not read the docs
> > that way), but I guess I was expecting it to see that "upper(name)" isn't
> > there, so it should pull that expression apart, find "name" and see that in
> > the output list before it starts searching the input list. After all,
> > that's what happens when it wants to search the input list, it's torn the
> > expression apart to find a column name. So why did it not look for "name"
> > in the output list but was willing to do that for the input list. I guess
> > that was really the heart of my question. :)
> >
> This probably comes up twice a year or so.  The depth of detail of the
> answer depends on who decided to respond.  No ones seem motivated enough
> to write a decent FAQ article...and enough people are willing to just
> answer to the (public/searchable)
>
> Here's a decent context response by Tom Lane that I quickly found from a
> few years back.
>
> https://www.postgresql.org/message-id/12023.1376506569%40sss.pgh.pa.us

Thanks David! That explains it even more and how it got this way.

I'll see about finding a few spare cycles to create a doc patch based on Tom's answer and maybe it'll get accepted and
helpothers down the road. 

Kevin