Re: Re: Reusing abbreviated keys during second pass of ordered [set] aggregates

On Wed, Dec 9, 2015 at 5:15 PM, Peter Geoghegan <pg(at)heroku(dot)com> wrote:
> On Wed, Dec 9, 2015 at 11:31 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> I find the references to a "void" representation in this patch to be
>> completely opaque. I see that there are some such references in
>> tuplesort.c already, and most likely they were put there by commits
>> that I did, so I guess I have nobody but myself to blame, but I don't
>> know what this means, and I don't think we should let this terminology
>> proliferate.
>>
>> My understanding is that the "void" representation is intended to
>> whatever Datum we originally got, which might be a pointer. Why not
>> just say that instead of referring to it this way?
>
> That isn't what is intended. "void" is the state that macros like
> index_getattr() leave NULL leading attributes (that go in the
> SortTuple.datum1 field) in.

What kind of state is that? Can't we define this in terms of what it
is rather than how it gets that way?

--
Robert Haas
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