E.5. Postgres Pro Standard 15.4.1

Release Date: 2023-08-18

E.5.1. Overview

This release is based on PostgreSQL 15.4 and Postgres Pro Standard 15.3.2. All improvements inherited from PostgreSQL 15.4 are listed in PostgreSQL 15.4 Release Notes. Other major changes and enhancements are as follows:

  • Added the generic_plan_fuzz_factor configuration parameter. This parameter sets the plan cost calculation coefficient of the planner, which increases the probability that the generic or custom plan will be selected more often.

  • Added the enable_appendorpath configuration parameter, which enables the Append plan for OR clauses. It is useful for applications with auto-generated queries.

  • Added support for Debian 12 and ended support for Debian 9.

  • Fixed a segmentation fault, which occurred during SELECT queries and was caused by an oversight in the previous bugfix related to self join removal optimization.

  • Fixed an outdated recommendation to customize a unit file in the postgrespro-std-15.service file comments.

  • Fixed the optimizer estimation of the number of tuples with the same hash key. The optimizer did not take into account that in a join by a large number of columns, the number of unique hash keys must rapidly grow, considered the number of hash keys to be small and finally chose merge join instead of hash join.

  • Fixed usage of the joinsel component, which is needed for a more accurate cardinality estimation by several columns. If for some reason (for example, because of insufficient detailed statistics) joinsel cannot make a good prediction, Postgres Pro will not use joinsel in this particular case, but estimate cardinality using a regular algorithm. If joinsel has to estimate cardinality by a single column, a regular algorithm will also be used instead.

  • Fixed a bug that did not allow storing data of the mchar, mvarchar types larger than 250 MB. Now up to 1 GB of data of these types can be stored correctly.

  • Upgraded pg_probackup to version 2.6.5, which provides optimizations and bug fixes.

    • An attempt of a partial restore to a non-empty PGDATA directory now completes with an error, but a possibility of such a restore is retained with the --destroy-all-other-dbs flag specified.

    • Fixed inclusion of allocated but empty pages in an incremental backup.

    • Fixed point-in-time recovery issues:

      • Restore on the recovery time specified by the pg_probackup show command

      • Restore from backups with the --recovery-target-timeline and --no-validate options

    • Renamed the --skip-if-exist flag to --skip-if-exists

  • Upgraded pgpro_pwr to version 4.2, which adds interactive features to the report.

  • Upgraded PTRACK to version 2.5 Enterprise.

E.5.2. Migration to Version 15.4.1

If you are upgrading from Postgres Pro Standard based on the same PostgreSQL major version, it is enough to install the new version into your current installation directory.

When upgrading to Postgres Pro versions starting with 15.3.1, make sure to upgrade pg_probackup to version 2.6.3 or higher since lower versions are incompatible with these Postgres Pro versions.

To migrate from PostgreSQL or a Postgres Pro Standard release based on a previous PostgreSQL major version, see the instructions in Postgres Pro Standard 15.0.1 Release Notes.