Re: More WITH

On Fri, Aug 21, 2015 at 2:39 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Tue, Aug 18, 2015 at 11:23 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> More generally, what would you hope to accomplish with such a construct
>>> that wouldn't be better done by writing the cursor's underlying query
>>> directly in the WITH clause?
>
>> Maybe I'm stupid today, but it seems like the obvious use case would
>> be fetching some but not all rows from the cursor?
>
> And how many rows would that be? As I said, the proposed syntax leaves
> it completely unclear how many rows get fetched or what the ending cursor
> position is; but especially so if you want the answer to be something
> other than "all/the end".

/me is bemused.

The existing syntax for FETCH already includes a way to specify the
number of rows you want to fetch, as in this example from the
documentation:

FETCH FORWARD 5 FROM liahona;

Why wouldn't that work here too?

--
Robert Haas
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