Re: Function Column Expansion Causes Inserts To Fail

On Tue, May 31, 2011 at 5:01 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Merlin Moncure <mmoncure@gmail.com> writes:
>> I've never taken the time to really get my head around 'lateral'
>> enough to say for sure if it provides clean workarounds for all the
>> cases that get people into hot water.  The case that used to get me a
>> lot is (the unfortunately generally under utilized) custom aggregates.
>
>> problem:
>> select bar_id, (some_agg(foo)).* from foo join bar ... group by bar_id;
>
> Hm, really?  I'd expect that nodeAgg's attempts to collect identical
> aggregate calls into one would keep you out of trouble there.  That
> hack unfortunately doesn't generalize to ordinary functions ...

you appear to be right -- memory failing here.

merlin