Re: COPY as a set returning function

On 15 Oct. 2016 04:56, "Corey Huinker" <corey(dot)huinker(at)gmail(dot)com> wrote:

> I would like to make COPY itself a SRF. That's a bit beyond my
capabilities, so if that is the route we want to go, I will need help.
>
> The syntax would probably look like this (new bits in bold):
>
>> WITH my_copy AS (
>> COPY FROM 'example.csv' TO RESULT SET(c1 text, c2 integer, dummy1
text, dummy2 text, c5 date) WITH (FORMAT CSV)
>> RETURNING c1, c2, c3
>> )

Strong -1 from me on this approach. Our CTE implementation materializes
everything so this is no better than COPYing to a temp table.

Not unless you plan to fix that (and figure out the backward compatibility
issues since the bug is documented as a feature) or implement RETURNING in
subqueries... I'd go for the function.