On Fri, 2003-09-19 at 06:12, Greg Stark wrote:
> Tom Lane <[EMAIL PROTECTED]> writes:
>
> > I think this is a pipe dream. Variation in where the data gets laid
> > down on your disk drive would alone create more than that kind of delta.
> > I'm frankly amazed you could get repeatability within 2-
On Thu, 2003-09-18 at 20:20, Tom Lane wrote:
> Jenny Zhang <[EMAIL PROTECTED]> writes:
> > ... It seems to me that small
> > effective_cache_size favors the choice of nested loop joins (NLJ)
> > while the big effective_cache_size is in favor of merge joins (MJ).
>
> No, I wouldn't think that,
I posted more results as you requested:
On Fri, 2003-09-19 at 08:08, Manfred Koizar wrote:
> On Thu, 18 Sep 2003 15:36:50 -0700, Jenny Zhang <[EMAIL PROTECTED]>
> wrote:
> >We thought the large effective_cache_size should lead us to better
> >plans. But we found the opposite.
>
> The common str
On Thu, 18 Sep 2003 15:36:50 -0700, Jenny Zhang <[EMAIL PROTECTED]>
wrote:
>We thought the large effective_cache_size should lead us to better
>plans. But we found the opposite.
The common structure of your query plans is:
Sort
Sort Key: sum((partsupp.ps_supplycost * partsupp.ps_availqty))
Tom Lane <[EMAIL PROTECTED]> writes:
> I think this is a pipe dream. Variation in where the data gets laid
> down on your disk drive would alone create more than that kind of delta.
> I'm frankly amazed you could get repeatability within 2-3%.
I think the reason he gets good repeatability is be
> I put the EXPLAIN ANALYZE output at:
> http://developer.osdl.org/~jenny/large_explain_analyze
> http://developer.osdl.org/~jenny/small_explain_analyze
> The actual execution time is 37 seconds(large) vs 5 seconds (small).
>
There's an obvious row count misestimation in the 'large' plan:
-> So
On Thu, 18 Sep 2003 12:27:23 -0700 (GMT-07:00), LN Cisneros
<[EMAIL PROTECTED]> wrote:
>But, the EXISTS version doesn't
Laurette,
looking at that SELECT statement again I can't see what's wrong with
it. One of us is missing something ;-)
> really give me what I want...
Can you elaborate?
SELEC
