lolor

lolor : Logical-replication-friendly replacement for PostgreSQL large objects

Overview

Packages

Source

pig build pkg lolor;		# 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 lolor;		# install via package name, for the active PG version

pig install lolor -v 17;   # install for PG 17

Create this extension with:

CREATE EXTENSION lolor;

Usage

lolor: Logical-replication-friendly replacement for PostgreSQL large objects

Makes PostgreSQL large objects compatible with logical replication by storing them in non-catalog tables.

Enabling

CREATE EXTENSION lolor;

Configure the node identifier in postgresql.conf:

lolor.node = 1  -- unique node ID (1 to 2^28)

Optionally adjust the search path:

SET search_path = lolor, "$user", public, pg_catalog;

Large Object Operations

Once installed, the standard lo_* functions are redirected to use lolor’s tables:

-- Create a large object
SELECT lo_create(0);

-- Import a file into a large object
SELECT lo_import('/path/to/file.bin');

-- Export a large object to a file
SELECT lo_export(oid, '/path/to/output.bin');

-- Open, read, write, seek, close
SELECT lo_open(oid, x'40000'::int);  -- INV_WRITE
SELECT lowrite(fd, 'data'::bytea);
SELECT loread(fd, 1024);
SELECT lo_close(fd);

-- Delete a large object
SELECT lo_unlink(oid);

Replication Setup

Add lolor tables to your replication set:

-- For spock/pgedge replication
SELECT spock.repset_add_table('default', 'lolor.pg_largeobject');
SELECT spock.repset_add_table('default', 'lolor.pg_largeobject_metadata');

Internal Tables

The extension manages large objects in:

• lolor.pg_largeobject - stores object data chunks
• lolor.pg_largeobject_metadata - stores object metadata

Limitations

• Native PostgreSQL large object functionality cannot be used while lolor is active
• Migration of existing native large objects to lolor is not supported
• ALTER LARGE OBJECT, GRANT ON LARGE OBJECT, COMMENT ON LARGE OBJECT, and REVOKE ON LARGE OBJECT are not supported
• Requires PostgreSQL 16 or newer