Re: COPY FROM WHEN condition

On Wed, 30 Jan 2019 at 10:12, Andres Freund <andres@anarazel.de> wrote:
>
> On 2019-01-30 10:05:35 +1300, David Rowley wrote:
> > On Wed, 30 Jan 2019 at 04:22, Andres Freund <andres@anarazel.de> wrote:
> > > I think I might have a patch addressing the problem incidentally. For pluggable storage I slotified copy.c, which
alsoremoves the first heap_form_tuple. Quite possible that nothing more is needed. I've removed the batch context
altogetherin yesterday's rebase, there was no need anymore. 
> >
> > In your patch, where do the batched tuples get stored before the heap
> > insert is done?
>
> There's one slot for each batched tuple (they are reused). Before
> materialization the tuples solely exist in tts_isnull/values into which
> NextCopyFrom() directly parses the values.  Tuples never get extracted
> from the slot in copy.c itself anymore, table_multi_insert() accepts
> slots.  Not quite sure whether I've answered your question?

I think so.  I imagine that should also speed up COPY WHERE too as
it'll no longer form a tuple before possibly discarding it.

--
 David Rowley                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services