On Fri, May 7, 2010 at 11:35 AM, Tom Lane wrote:
> "Kevin Grittner" writes:
>> Alexander Korotkov wrote:
I just don't find why it is coincidence. I think that such plan
will always produce result ordered by two columns, because such
nested index scan always produce this result.
>
"Kevin Grittner" writes:
> Alexander Korotkov wrote:
>>> I just don't find why it is coincidence. I think that such plan
>>> will always produce result ordered by two columns, because such
>>> nested index scan always produce this result.
> Assuming a nested index scan, or any particular plan,
Alexander Korotkov wrote:
> Alexander Korotkov wrote:
>>> Well, no, because that plan wouldn't produce the specified
>>> ordering; or at least it would be a lucky coincidence if it did.
>>> It's only sorting on t1.value.
>>>
>> I just don't find why it is coincidence. I think that such plan
>>
I found my mistake. My supposition is working only if value column in t1
table is unique. But if I replace the index by unique one then plan is the
same.
On Mon, May 3, 2010 at 5:57 PM, Alexander Korotkov wrote:
> Well, no, because that plan wouldn't produce the specified ordering;
>> or at least
>
> Well, no, because that plan wouldn't produce the specified ordering;
> or at least it would be a lucky coincidence if it did. It's only
> sorting on t1.value.
>
I just don't find why it is coincidence. I think that such plan will always
produce result ordered by two columns, because such neste
=?KOI8-R?B?68/Sz9TLz9cg4czFy9PBzsTS?= writes:
> So PostgreSQL planner can produce the plan I need but it doesn't produce
> this plan when I specify particular second ordering column.
Well, no, because that plan wouldn't produce the specified ordering;
or at least it would be a lucky coincidence i
Hello, everybody!
I'm using PostgreSQL 8.4.3, compiled by Visual C++ build 1400, 32-bit on
Windows XP SP3.
I use following data model for issue reproducing.
CREATE TABLE test1
(
id integer NOT NULL,
"value" double precision,
CONSTRAINT test1_pkey PRIMARY KEY (id)
);
CREATE INDEX test1_valu
