Re: [HACKERS] Performance testing of COPY (SELECT) TO

Andrew Dunstan írta:
> Alvaro Herrera wrote:
>> Böszörményi Zoltán wrote:
>>
>>> Hi,
>>>
>>> what's the problem with COPY view TO, other than you don't like it? :-)
>>>
>>
>> The problem is that it required a ugly piece of code.  Not supporting it
>> means we can keep the code nice.  The previous discussion led to this
>> conclusion anyway so I don't know why we are debating it again.
>>
>>
>
> What is so ugly about it? I haven't looked at the code, but I am
> curious to know.
>
> I also don't recall the consensus being quite so clear cut. I guess
> there is a case for saying that if it's not allowed then you know that
> "COPY relname TO" is going to be fast. But, code aesthetics aside, the
> reasons for disallowing it seem a bit thin, to me.
>
> cheers
>
> andrew
>

I would say the timing difference between
"COPY table TO" and "COPY (SELECT * FROM table) TO"
was  noise, so it's not even faster.

And an updatable VIEW *may* allow COPY view FROM...


Best regards,
Zoltán Böszörményi