Re: Number of rows in a cursor ?

On Thu, Aug 25, 2005 at 08:51:59 +0200, Bo Lorentsen <bl@netgroup.dk> wrote:
> Michael Fuhr wrote:
> 
> >Right -- when you open a cursor PostgreSQL doesn't know how many
> >rows it will return.  PostgreSQL selects a query plan based on an
> >*estimate* of how many rows the query will return, but until you
> >fetch all the rows you can't know for sure how many rows there will
> >be.
> > 
> >
> So if i make a but data set as result of a cursor I only "pay" for the 
> rows I actually fetch ?

There is usually some overhead for set up, though I believe quick starting
plans are favored for cursor queries.