Thread: Copy paste error

Copy paste error

From
PG Doc comments form
Date:
The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/17/multivariate-statistics-examples.html
Description:

CREATE STATISTICS stts (dependencies) ON a, b FROM t;
ANALYZE t;
EXPLAIN (ANALYZE, TIMING OFF) SELECT * FROM t WHERE a = 1 AND b = 1;
                                  QUERY PLAN
-------------------------------------------------------------------​------------
 Seq Scan on t  (cost=0.00..195.00 rows=100 width=8) (actual rows=100
loops=1)
   Filter: ((a = 1) AND (b = 1))
   Rows Removed by Filter: 9900


The result of the explain is a copy paste of previous example, so this
example looks like the statistic doesn't improve things

Re: Copy paste error

From
"David G. Johnston"
Date:
On Thu, Feb 13, 2025 at 7:44 AM PG Doc comments form <noreply@postgresql.org> wrote:
The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/17/multivariate-statistics-examples.html
Description:

CREATE STATISTICS stts (dependencies) ON a, b FROM t;
ANALYZE t;
EXPLAIN (ANALYZE, TIMING OFF) SELECT * FROM t WHERE a = 1 AND b = 1;
                                  QUERY PLAN
-------------------------------------------------------------------------------
 Seq Scan on t  (cost=0.00..195.00 rows=100 width=8) (actual rows=100
loops=1)
   Filter: ((a = 1) AND (b = 1))
   Rows Removed by Filter: 9900


The result of the explain is a copy paste of previous example, so this
example looks like the statistic doesn't improve things

Look more closely, and read the surrounding text.  It talks about the problem being the rows estimate.

David J.

Re: Copy paste error

From
David Emmerson
Date:
Man... I looked at it 50 times before I posted that report. Sorry!

Totally correct. Nothing to see here.

On Thu, 13 Feb 2025 at 14:49, David G. Johnston <david.g.johnston@gmail.com> wrote:
On Thu, Feb 13, 2025 at 7:44 AM PG Doc comments form <noreply@postgresql.org> wrote:
The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/17/multivariate-statistics-examples.html
Description:

CREATE STATISTICS stts (dependencies) ON a, b FROM t;
ANALYZE t;
EXPLAIN (ANALYZE, TIMING OFF) SELECT * FROM t WHERE a = 1 AND b = 1;
                                  QUERY PLAN
-------------------------------------------------------------------------------
 Seq Scan on t  (cost=0.00..195.00 rows=100 width=8) (actual rows=100
loops=1)
   Filter: ((a = 1) AND (b = 1))
   Rows Removed by Filter: 9900


The result of the explain is a copy paste of previous example, so this
example looks like the statistic doesn't improve things

Look more closely, and read the surrounding text.  It talks about the problem being the rows estimate.

David J.