On Fri, Feb 29, 2008 at 05:28:29PM +0530, Gurjeet Singh wrote:
> On Fri, Feb 29, 2008 at 3:55 PM, Martijn van Oosterhout <kleptog(at)svana(dot)org> wrote:
> > Except if you have an index on the column you're ordering by. Then the
> > server can really return the first row quickly.
> Quickly for sure... but I don't think 'without processing all the rows that
Postgres will always try to do the smallest amount of work possible.
Putting a LIMIT in will cause the planner to pick a plan that returns an
appropriate number of rows quickly, sometimes it can be a very different
> I think it will still process all the rows and return just one.
How do you explain that when you run:
SELECT 1/v FROM (VALUES (1),(0)) c(v);
Without a limit you get a "division by zero" exception, and when you
have a limit of one row you get a result back.
In response to
pgsql-general by date
|Next:||From: Scott Marlowe||Date: 2008-02-29 14:15:45|
|Subject: Re: rule question|
|Previous:||From: Gurjeet Singh||Date: 2008-02-29 11:58:29|
|Subject: Re: LIMIT Question|