I missed it completely, but on 24th of March 2017, Alvaro Herrera committed patch: Implement multivariate n-distinct coefficients Add support for explicitly declared statistic objects (CREATE STATISTICS), allowing collection of statistics on more complex combinations that individual table columns. Companion commands DROP STATISTICS and ...

On 27th of March, Andrew Dunstan committed patch: Add stats for min, max, mean, stddev times to pg_stat_statements. The new fields are min_time, max_time, mean_time and stddev_time. Based on an original patch from Mitsumasa KONDO, modified by me. Reviewed by Petr Jelínek.

On 28th of January, Fujii Masao committed patch: Add pg_stat_archiver statistics view. This view shows the statistics about the WAL archiver process's activity. Gabriele Bartolini, reviewed by Michael Paquier, refactored a bit by me.

In previous posts in this series, I talked about how to read EXPLAIN output, and what each line (operation/node) means. Now, in the final post, I will try to explain how it happens that Pg chooses "Operation X" over "Operation Y".

On 26th of January, Magnus Hagander committed patch: Adds a counter that tracks number of deadlocks that occurred in each database to pg_stat_database. Magnus Hagander, reviewed by Jaime Casanova

On 26th of January, Magnus Hagander committed patch: Add counters for number and size of temporary files used for spill-to-disk queries for each database to the pg_stat_database view. Tomas Vondra, review by Magnus Hagander

June 11th, 2011 by depesz | Tags: , , , , , , | Comments Off on explain.depesz.com – new feature and some new stats

First of all, as of today, I added new feature, called anonymization. It is for all of the people who are afraid that their plans contain information that they don't want to (or can't) share on the internet. It works like this:

March 2nd, 2011 by depesz | Tags: , , , , , | Comments Off on Waiting for 9.1 – stats reset tracking

On 10th of February, Magnus Hagander committed patch: Track last time for statistics reset on databases and bgwriter Tracks one counter for each database, which is reset whenever the statistics for any individual object inside the database is reset, and one counter for ...

Robert Haas wrote, and Tom Lane committed (on 2nd of August) patch which adds interesting capability: Log Message: ----------- Add ALTER TABLE ... ALTER COLUMN ... SET STATISTICS DISTINCT Robert Haas Log message is rather terse, so what does it exactly do?

Today another great patch, committed by Tom Lane. This patch was written by Martin Pihlak (with some edits by Tom).