Fujii Masao e64aa1a39d doc: Clarify when backend_xmin in pg_stat_replication can be NULL.
Improve the documentation of pg_stat_replication to explain when
the backend_xmin column becomes NULL. This happens when
a replication slot is used (the xmin is then shown in pg_replication_slots)
or when hot_standby_feedback is disabled.

Author: Renzo Dani <arons7@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CA+XOKQAMXzskpdUmj2sg03_5fmiXc2Gs0r3TX1_rmcFcqh+=xQ@mail.gmail.com
2025-10-17 14:03:42 +09:00
2025-08-14 12:09:34 -04:00
2025-08-15 10:32:35 +02:00

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.

Copyright and license information can be found in the file COPYRIGHT.

General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.

The latest version of this software, and related 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
he World's Most Advanced Open Source Relational Database.
Readme 789 MiB
Languages
C 84.9%
PLpgSQL 6.2%
Perl 4.6%
Yacc 1.2%
Meson 0.7%
Other 2.2%