> >> The best solution is probably to put a LIMIT into the DECLARE
CURSOR,
> >> so that the planner can see how much you intend to fetch.
> I assume that this limits the resultset to a LIMIT. That is not what I
was
> hoping for. I was hoping for a way to scrolll throught the whole
tables
> with orders.
>
> I have tested, and if one really wants the whole table the query with
"set
> enable_seqscan = on" lasts 137 secs, the query with "set
enable_seqscan =
> off" lasts 473 secs, so (alas), the planner is right.
>
> I sure would like to have ISAM like behaviour once in a while.
Then stop using cursors. A few months back I detailed the relative
merits of using Cursors v. Queries to provide ISAM like functionality
and Queries win hands down. Right now I am using pg as an ISAM backend
for a relatively old and large COBOL ERP via a C++ ISAM driver, for
which a publicly available version of the source will be available Real
Soon Now :-).
Merlin