pgrdf

pgrdf : RDF, SPARQL, SHACL, and OWL reasoning for PostgreSQL

Overview

Packages

Source

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

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

Config this extension to shared_preload_libraries:

shared_preload_libraries = 'pgrdf';

Create this extension with:

CREATE EXTENSION pgrdf;

Usage

Sources:

• 0.6.40 release
• pgrdf.control
• README.md
• Cargo.toml
• guide/01-install.md
• guide/tour.md
• guide/05-graphs.md
• guide/06-validation-recipes.md
• 0.6.39 to 0.6.40 upgrade

pgrdf 0.6.40 stores RDF graphs in PostgreSQL with Turtle/TriG/N-Quads ingestion, SPARQL queries and updates, SHACL validation, and RDFS/OWL reasoning. Preload pgrdf and restart before creating the extension as a superuser.

Core Workflow

shared_preload_libraries = 'pgrdf'

CREATE EXTENSION pgrdf;
SELECT pgrdf.add_graph('http://example.org/people');
SELECT pgrdf.parse_turtle(
  '@prefix ex: <http://example.org/> . ex:alice ex:name "Alice" .',
  pgrdf.graph_id('http://example.org/people'));
SELECT * FROM pgrdf.sparql('SELECT ?s ?p ?o WHERE { ?s ?p ?o } LIMIT 10');
SELECT * FROM pgrdf.surface();

Operational Boundaries

The fixed pgrdf schema provides add_graph, graph_id, parse_turtle, load_turtle, sparql, materialize, validate, stats and surface. File loaders read server-side paths; grant access deliberately. can_clear_graphs() reports graph-clear privileges. Non-owner graph writes require the documented underlying table grants; graph locks still apply. shacl_capability() reports the supported validation surface, and path-depth/truncation settings bound traversal. Source features cover PostgreSQL 14–18; published Linux binaries target PG18. Version 0.6.39 allocates graph IDs from a non-reusing sequence; the IRI is the graph identity, and gaps are normal. After installing the matching library, run ALTER EXTENSION pgrdf UPDATE in each database. A newer library rejects old SQL with SQLSTATE 55000. Do not use the broken 0.6.35–0.6.38 PGXN source archives. Preserve graph/dictionary data together in verified backups.

Ownership Repair in 0.6.40

The 0.6.39 upgrade could leave _pgrdf_graph_id_seq owned by the upgrade executor after storage tables had been transferred to another role, preventing new graph creation. Version 0.6.40 aligns that sequence with the owner of _pgrdf_quads; granting sequence usage alone is insufficient. pgrdf.ownership_drift() reports mismatched storage owners and proposed repair commands. Review them before applying role changes. Upgrade SQL in each database after installing matching binaries; versions 0.6.34–0.6.38 can upgrade directly to 0.6.40.