Re: LEFT JOINs not optimized away when not needed

On Tue, Jul 8, 2014 at 5:40 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Moshe Jacobson <moshe@neadwerx.com> writes:
>> On Tue, Jul 8, 2014 at 4:40 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> No.  There is nothing about GROUP BY in the join removal logic.
>
>> OK. Thank you. Is this something that would make sense to add?
>
> Dunno.  I don't recall any previous requests for such a thing, so I'd not
> be inclined to add it unless it can be done very cheaply (in terms of both
> code and runtime).

I thought this was exactly what was being discussed on the "Allowing
join removals for more join types" thread.

--
Robert Haas
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