din
Отправлено: 27 апреля 2022 г. 13:08:22
Кому: Пантюшин Александр Иванович
Копия: pgsql-hack...@postgresql.org; Тарасов Георгий Витальевич
Тема: Re: Wrong rows count in EXPLAIN
Hi!
> 26 апр. 2022 г., в 13:45, Пантюшин Александр Иванович
> написал(а):
>
> When I create a new table, and
On Wed, Apr 27, 2022 at 09:44:21AM -0400, Tom Lane wrote:
> =?koi8-r?B?8MHO1MDbyc4g4czFy9PBzsTSIOnXwc7P18ne?=
> writes:
> > When I create a new table, and then I evaluate the execution of the SELECT
> > query, I see a strange rows count in EXPLAIN
> > CREATE TABLE test1(f INTEGER PRIMARY KEY
=?koi8-r?B?8MHO1MDbyc4g4czFy9PBzsTSIOnXwc7P18ne?=
writes:
> When I create a new table, and then I evaluate the execution of the SELECT
> query, I see a strange rows count in EXPLAIN
> CREATE TABLE test1(f INTEGER PRIMARY KEY NOT NULL);
> ANALYZE test1;
> EXPLAIN SELECT * FROM test1;
>
On Wed, 27 Apr 2022 at 21:08, Andrey Borodin wrote:
> Which Postgres version do you use?
3d351d91 changed things so we could tell the difference between a
relation which was analyzed and is empty vs a relation that's never
been analyzed. That's why you're not seeing the same behaviour as the
OP.
> 27 апр. 2022 г., в 15:17, Пантюшин Александр Иванович
> написал(а):
>
> Hi,
> >Which Postgres version do you use?
> I checked this on PG 11
> ...
> and on PG 13
Yes, I think before 3d351d91 it was impossible to distinguish between actually
empty and never analyzed table.
But now it is
Hi!
> 26 апр. 2022 г., в 13:45, Пантюшин Александр Иванович
> написал(а):
>
> When I create a new table, and then I evaluate the execution of the SELECT
> query, I see a strange rows count in EXPLAIN
> CREATE TABLE test1(f INTEGER PRIMARY KEY NOT NULL);
> ANALYZE test1;
> EXPLAIN SELECT *
When I create a new table, and then I evaluate the execution of the SELECT
query, I see a strange rows count in EXPLAIN
CREATE TABLE test1(f INTEGER PRIMARY KEY NOT NULL);
ANALYZE test1;
EXPLAIN SELECT * FROM test1;
QUERY PLAN
