Обсуждение: Distinct tightly coupled with Agg

Hello,

I am looking at todo item (#1) Implement DISTINCT clause in window aggregates and while looking at code, I found distinct tightly coupled with Agg function. Looking at another todo item(#2) Do we really need so much duplicated code between Agg and WindowAgg?  I was wondering what is general stance on this? Is #2 per-requisite for #1?

If that is not case, I assume making distinct a standalone piece should be an option too?

Would be glad if someone should shed light on this. Thanks.

Regards,
Ankit

On 16/11/22 00:26, Tom Lane wrote:
> Ankit Kumar Pandey <itsankitkp@gmail.com> writes:
>> I am looking at todo item (#1) /Implement DISTINCT clause in window
>> aggregates/ and while looking at code, I found distinct tightly coupled
>> with Agg function. Looking at another todo item(#2) /Do we really need
>> so much duplicated code between Agg and WindowAgg/?  I was wondering
>> what is general stance on this? Is #2 per-requisite for #1?
> No, I think #2 is just a general statement of annoyance.  It'd be
> great if someone finds a way to refactor things to improve that; but
> seeing that window functions operate in a much different environment
> than plain aggregates, I'm not holding my breath.  It's certainly
> not a prerequisite for any other work in the area.
>
>             regards, tom lane

Makes sense, thank you.

Regards,

Ankit

Ankit Kumar Pandey <itsankitkp@gmail.com> writes:
> I am looking at todo item (#1) /Implement DISTINCT clause in window 
> aggregates/ and while looking at code, I found distinct tightly coupled 
> with Agg function. Looking at another todo item(#2) /Do we really need 
> so much duplicated code between Agg and WindowAgg/?  I was wondering 
> what is general stance on this? Is #2 per-requisite for #1?

No, I think #2 is just a general statement of annoyance.  It'd be
great if someone finds a way to refactor things to improve that; but
seeing that window functions operate in a much different environment
than plain aggregates, I'm not holding my breath.  It's certainly
not a prerequisite for any other work in the area.

            regards, tom lane