pg_statement_rollback

Overview

Version

Build

You can build the RPM / DEB packages for pg_statement_rollback using pig build:

pig build pkg pg_statement_rollback         # build RPM / DEB packages

Install

You can install pg_statement_rollback directly. First, make sure the PGDG and PIGSTY repositories are added and enabled:

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

Install the extension using pig or apt/yum/dnf:

pig install pg_statement_rollback;          # Install for current active PG version

pig ext install -y pg_statement_rollback -v 18  # PG 18
pig ext install -y pg_statement_rollback -v 17  # PG 17
pig ext install -y pg_statement_rollback -v 16  # PG 16
pig ext install -y pg_statement_rollback -v 15  # PG 15
pig ext install -y pg_statement_rollback -v 14  # PG 14

dnf install -y pg_statement_rollback_18       # PG 18
dnf install -y pg_statement_rollback_17       # PG 17
dnf install -y pg_statement_rollback_16       # PG 16
dnf install -y pg_statement_rollback_15       # PG 15
dnf install -y pg_statement_rollback_14       # PG 14

apt install -y postgresql-18-pg-statement-rollback   # PG 18
apt install -y postgresql-17-pg-statement-rollback   # PG 17
apt install -y postgresql-16-pg-statement-rollback   # PG 16
apt install -y postgresql-15-pg-statement-rollback   # PG 15
apt install -y postgresql-14-pg-statement-rollback   # PG 14

Preload:

shared_preload_libraries = 'pg_statement_rollback';

Usage

Sources:

• pg_statement_rollback v1.6 README
• Changes from v1.5 to v1.6

pg_statement_rollback keeps an explicit transaction usable after a statement error by creating an automatic savepoint before each eligible statement. It emulates the statement-level rollback behavior familiar from some other databases, but the client must still issue ROLLBACK TO SAVEPOINT after an error.

The module is loaded into a backend and does not require CREATE EXTENSION.

Load the Module

Load it for one session:

LOAD 'pg_statement_rollback.so';

For a selected role or database, add it to session_preload_libraries and reconnect:

session_preload_libraries = 'pg_statement_rollback'

Use shared_preload_libraries only if the deployment specifically needs server-wide loading; changing either preload list at server scope requires the corresponding restart or reconnect boundary.

Recover from a Failed Statement

BEGIN;
INSERT INTO accounts(id, balance) VALUES (1, 100);
INSERT INTO accounts(id, balance) VALUES (1, 200);
-- duplicate-key error
ROLLBACK TO SAVEPOINT "PgSLRAutoSvpt";
UPDATE accounts SET balance = 150 WHERE id = 1;
COMMIT;

The savepoint name is case-sensitive when quoted. Applications must detect the statement error and send the rollback command before continuing.

Configuration Index

• pg_statement_rollback.enabled enables automatic savepoints for the current session.
• pg_statement_rollback.savepoint_name changes the automatic savepoint name and is superuser-controlled.
• pg_statement_rollback.enable_writeonly limits savepoint creation to statements that can write.

Version 1.6 Behavior

Version 1.6 adds PostgreSQL 19 build support and improves detection of read-only transactions. The module no longer creates automatic savepoints in read-only transactions and releases its initial savepoint before SET TRANSACTION … READ ONLY, which avoids interfering with dump and other read-only sessions.

Caveats

• This is not transparent retry logic: clients must explicitly roll back to the automatic savepoint.
• Savepoints add overhead to every covered statement. Measure write-heavy workloads before enabling the module broadly.
• The upstream README warns of a crash with assertion-enabled PostgreSQL builds; do not treat development-build behavior as production-safe without testing.
• Transaction-wide errors, connection failures, and errors that invalidate the session cannot be repaired by a savepoint.