## E.5. Postgres Pro Standard 11.5.1

Release Date: 2019-08-09

### E.5.1. Overview

This release is based on PostgreSQL 11.5 and Postgres Pro Standard 11.4.1. All improvements inherited from PostgreSQL 11.5 are listed in PostgreSQL 11.5 Release Notes.

Major enhancements over Postgres Pro Standard 11.4.1 include:

- Added support for Debian 10.

- Added support for Red Hat Enterprise Linux 8.

- Backported an optimization for the `PostmasterIsAlive()` check. On Linux systems, backends now use signals to determine that postmaster has died. In particular, it fixes an issue with `pg_wal` bloating and high CPU load when logical replication with multiple publications and subscriptions is used. In vanilla PostgreSQL, this optimization appears in version 12.

- Improved planning accuracy for queries with `OR` clauses. Now sorting is performed correctly for such queries.

- Fixed implementation of greater than (>) and not equal to (<>) operators for the `jsquery` type.

### E.5.2. Migration to Version 11.5.1

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.

Since pg_probackup delivery model changed in Postgres Pro Standard 11.2.1, when upgrading from a lower version on ALT Linux and Debian-based systems, run `apt dist-upgrade` (or `apt-get dist-upgrade`) to ensure that all new dependencies are handled correctly. On Windows, you have to run a separate pg_probackup installer to complete the upgrade.

To migrate from PostgreSQL or a Postgres Pro Standard release based on a previous PostgreSQL major version, see the instructions in Postgres Pro Standard 11.1.1 Release Notes. If you are opting for a dump/restore, make sure to use the `--add-collprovider` option to correctly choose the provider for the default collation of the migrated database.