postgres/contrib/pg_stat_statements/sql/oldextversions.sql
Alexander Korotkov dc9f8a7983 Track statement entry timestamp in contrib/pg_stat_statements
This patch adds 'stats_since' and 'minmax_stats_since' columns to the
pg_stat_statements view and pg_stat_statements() function.  The new min/max
reset mode for the pg_stat_stetments_reset() function is controlled by the
parameter minmax_only.

'stat_since' column is populated with the current timestamp when a new
statement is added to the pg_stat_statements hashtable.  It provides clean
information about statistics collection time intervals for each statement.
Besides it can be used by sampling solutions to detect situations when a
statement was evicted and stored again between samples.

Such a sampling solution could derive any pg_stat_statements statistic values
for an interval between two samples with the exception of all min/max
statistics. To address this issue this patch adds the ability to reset
min/max statistics independently of the statement reset using the new
minmax_only parameter of the pg_stat_statements_reset(userid oid, dbid oid,
queryid bigint, minmax_only boolean) function. The timestamp of such reset
is stored in the minmax_stats_since field for each statement.
pg_stat_statements_reset() function now returns the timestamp of a reset as the
result.

Discussion: https://postgr.es/m/flat/72e80e7b160a6eb189df9ef6f068cce3765d37f8.camel%40moonset.ru
Author: Andrei Zubkov
Reviewed-by: Julien Rouhaud, Hayato Kuroda, Yuki Seino, Chengxi Sun
Reviewed-by: Anton Melnikov, Darren Rush, Michael Paquier, Sergei Kornilov
Reviewed-by: Alena Rybakina, Andrei Lepikhov
2023-11-27 02:52:17 +02:00

59 lines
2.2 KiB
SQL

-- test old extension version entry points
CREATE EXTENSION pg_stat_statements WITH VERSION '1.4';
-- Execution of pg_stat_statements_reset() is granted only to
-- superusers in 1.4, so this fails.
SET SESSION AUTHORIZATION pg_read_all_stats;
SELECT pg_stat_statements_reset();
RESET SESSION AUTHORIZATION;
AlTER EXTENSION pg_stat_statements UPDATE TO '1.5';
-- Execution of pg_stat_statements_reset() should be granted to
-- pg_read_all_stats now, so this works.
SET SESSION AUTHORIZATION pg_read_all_stats;
SELECT pg_stat_statements_reset();
RESET SESSION AUTHORIZATION;
-- In 1.6, it got restricted back to superusers.
AlTER EXTENSION pg_stat_statements UPDATE TO '1.6';
SET SESSION AUTHORIZATION pg_read_all_stats;
SELECT pg_stat_statements_reset();
RESET SESSION AUTHORIZATION;
SELECT pg_get_functiondef('pg_stat_statements_reset'::regproc);
-- New function for pg_stat_statements_reset introduced, still
-- restricted for non-superusers.
AlTER EXTENSION pg_stat_statements UPDATE TO '1.7';
SET SESSION AUTHORIZATION pg_read_all_stats;
SELECT pg_stat_statements_reset();
RESET SESSION AUTHORIZATION;
SELECT pg_get_functiondef('pg_stat_statements_reset'::regproc);
\d pg_stat_statements
SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
-- New functions and views for pg_stat_statements in 1.8
AlTER EXTENSION pg_stat_statements UPDATE TO '1.8';
\d pg_stat_statements
SELECT pg_get_functiondef('pg_stat_statements_reset'::regproc);
-- New function pg_stat_statement_info, and new function
-- and view for pg_stat_statements introduced in 1.9
AlTER EXTENSION pg_stat_statements UPDATE TO '1.9';
SELECT pg_get_functiondef('pg_stat_statements_info'::regproc);
\d pg_stat_statements
SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
-- New functions and views for pg_stat_statements in 1.10
AlTER EXTENSION pg_stat_statements UPDATE TO '1.10';
\d pg_stat_statements
SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
-- New functions and views for pg_stat_statements in 1.11
AlTER EXTENSION pg_stat_statements UPDATE TO '1.11';
\d pg_stat_statements
SELECT count(*) > 0 AS has_data FROM pg_stat_statements;
-- New parameter minmax_only of pg_stat_statements_reset function
SELECT pg_get_functiondef('pg_stat_statements_reset'::regproc);
DROP EXTENSION pg_stat_statements;