Michael Paquier 6da67a0c11 doc: Mention de-normalization of deallocated entries in pg_stat_statements
The current implementation of query normalization in pg_stat_statements
is optimistic.  If an entry is deallocated between the post-analyze hook
and the planner and/or execution hook, it can be possible to find query
strings with literal constant values (like "SELECT 1, 2") rather than
their normalized flavor (like "SELECT $1, $2").

This commit adds in the documentation a paragraph about this limitation,
and that this risk can be reduced by increasing pg_stat_statements.max,
particularly if pg_stat_statements_info reports a high number of
deallocations.

Author: Sami Imseih
Discussion: https://postgr.es/m/9CFF3512-355B-4676-8CCC-6CF622F4DC1A@amazon.com
2023-03-01 10:47:01 +09:00
2023-02-27 20:27:48 -05:00
2019-12-18 09:13:13 +01:00
2022-12-04 15:23:00 -05:00
2023-01-02 15:00:37 -05:00
2020-02-10 20:47:50 +01:00
2023-01-02 15:00:37 -05:00
2020-02-10 20:47:50 +01:00
2020-02-10 20:47:50 +01:00

PostgreSQL Database Management System
=====================================

This directory contains the source code distribution of the PostgreSQL
database management system.

PostgreSQL is an advanced object-relational database management system
that supports an extended subset of the SQL standard, including
transactions, foreign keys, subqueries, triggers, user-defined types
and functions.  This distribution also contains C language bindings.

PostgreSQL has many language interfaces, many of which are listed here:

	https://www.postgresql.org/download/

See the file INSTALL for instructions on how to build and install
PostgreSQL.  That file also lists supported operating systems and
hardware platforms and contains information regarding any other
software packages that are required to build or run the PostgreSQL
system.  Copyright and license information can be found in the
file COPYRIGHT.  A comprehensive documentation set is included in this
distribution; it can be read as described in the installation
instructions.

The latest version of this software may be obtained at
https://www.postgresql.org/download/.  For more information look at our
web site located at https://www.postgresql.org/.
Description
No description provided
Readme 671 MiB
Languages
C 85.7%
PLpgSQL 5.8%
Perl 4.1%
Yacc 1.3%
Makefile 0.7%
Other 2.3%