timezone_abbreviations — PostgreSQL configuration parameter

Sets the collection of additional time zone abbreviations that will be accepted by the server for datetime input (beyond any abbreviations defined by the current TimeZone setting).

At a glance

What it does

Sets the collection of additional time zone abbreviations that will be accepted by the server for datetime input (beyond any abbreviations defined by the current TimeZone setting). The default is ‘Default’, which is a collection that works in most of the world; there are also ‘Australia’ and ‘India’, and other collections can be defined for a particular installation. See datetime_config_files for more information.

(Description quoted from the official PostgreSQL documentation.)

How to apply a change

Can be set per session with SET, per role/database with ALTER ROLE/DATABASE ... SET, or globally in postgresql.conf.

Inspect the current value and source with SHOW timezone_abbreviations; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'timezone_abbreviations';.

Tuning guidance

This sets a session default (locale, formatting, search path or transaction behaviour) rather than a performance knob. Set it per role or database with ALTER ROLE/DATABASE ... SET so the right default follows the right workload, and prefer setting it explicitly in the application for behaviour the query results depend on.

Reference

PostgreSQL documentation — timezone_abbreviations.