pg_variables

pg_variables : Session-scoped variables with scalar, array, and record types

Overview

Packages

Source

pig build pkg pg_variables;		# build rpm/deb

Install

Make sure PGDG and PIGSTY repo available:

pig repo add pgsql -u   # add both repo and update cache

Install this extension with pig:

pig install pg_variables;		# install via package name, for the active PG version

pig install pg_variables -v 18;   # install for PG 18
pig install pg_variables -v 17;   # install for PG 17
pig install pg_variables -v 16;   # install for PG 16
pig install pg_variables -v 15;   # install for PG 15
pig install pg_variables -v 14;   # install for PG 14

Create this extension with:

CREATE EXTENSION pg_variables;

Usage

• Sources: README, repository tags, control file

pg_variables provides session-scoped variables grouped into named packages. Variables live only in the current session and are non-transactional by default unless created with is_transactional := true.

Basic Set And Get

CREATE EXTENSION pg_variables;

SELECT pgv_set('vars', 'int1', 101);
SELECT pgv_get('vars', 'int1', NULL::int);

Transactional variables participate in savepoints and rollbacks:

BEGIN;
SELECT pgv_set('vars', 'trans_int', 101, true);
SAVEPOINT sp1;
SELECT pgv_set('vars', 'trans_int', 102, true);
ROLLBACK TO sp1;
COMMIT;

Core APIs

The README documents generic scalar and array APIs:

• pgv_set(package, name, value, is_transactional default false)
• pgv_get(package, name, NULL::type, strict default true)

It also documents record-oriented APIs:

• pgv_insert()
• pgv_update()
• pgv_delete()
• pgv_select()

Useful administration helpers include pgv_exists(), pgv_remove(), pgv_free(), pgv_list(), and pgv_stats().

Error And Strictness Behavior

pgv_get() checks both existence and type. The README shows that missing packages, missing variables, or mismatched types raise errors unless strict := false, in which case NULL is returned for missing values.

Deprecated Helpers And Version Note

Upstream still ships deprecated type-specific helpers such as pgv_set_int() / pgv_get_int() and pgv_set_jsonb() / pgv_get_jsonb(), but recommends the generic pgv_set() / pgv_get() API.

The repository tag is v1.2.5, while the current pg_variables.control file still declares default_version = '1.2'. That matches the packaging note that the release tag advanced without changing the SQL extension version string.