Re: pgsql/src/backend/nodes (copyfuncs.c outfuncs.c print.c)

Hiroshi Inoue <Inoue(at)tpf(dot)co(dot)jp> writes:
> begin;
> declare myc cursor for select * from t1 limit all;
> fetch 20 in myc; (the first page)
> ...(interaction)
> fetch 20 in myc; (the next page)
> ..(interaction)
> fetch backward 20 in myc; (the previous page)
> ...

> What I expect here is to get rows of each page in
> an average response time not the total throughput
> of db operation.

Yes, but why should the presence of "limit all" affect that?
It's not apparent to me why the optimizer should treat this
case differently from plain
declare myc cursor for select * from t1;

regards, tom lane