account_treeProcesses & flows
pgRDF's operating model is a set of composable verbs you chain with arrows. Some verbs are parallel and scale with the box; others are single-threaded and want a graph sized to your hardware. This section is the verb reference, the worked patterns, and the method for building your own chain.
Two kinds of process
Every verb falls into one of two classes, split by how it scales:
| Class | Verbs | Scaling |
|---|---|---|
| Parallel — scales with the box | Import, Seal | Fans across a background-worker pool. Add cores → goes faster. Proven on the full 8.2 B graph. |
| Single-threaded — sized to fit | Reason, Validate | Runs on one backend. The graph must fit your hardware — you do not reason over the full source graph. |
This is the constraint that shapes every chain: ingest is parallel, reasoning is not. So at scale you ingest the full graph in parallel, then carve a right-sized slice and reason over that.
The verbs
| Verb | Class | Status |
|---|---|---|
| Import | parallel | Shipped — staged bulk loader (load_turtle, load_turtle_staged_run). |
| Seal | parallel | Shipped — the index-build step (the staged loader's concurrent INDEX phase). |
| Query | per-query | Shipped — full SPARQL 1.1 surface. |
| Reason | single-threaded | Shipped — OWL 2 RL + RDFS materialization. |
| Validate | single-threaded | Shipped — SHACL Core 25/25. |
| Carve | parallel | Roadmap — C1/C2 (roadmap); manual path today. |
| Unload | — | Roadmap — C4 (roadmap); manual path today. |
The import-side and reasoning-side verbs are all shipped on v0.6.14. Carve and Unload are the verbs the v0.6.n line is building toward the v0.7.0 graduation.
The patterns
Four worked chains cover almost every process. Pick one with Choosing a process:
- search Load → Query — the simplest chain; queryable at any scale.
- psychology Load → Reason → Query — materialize the closure, then query it.
- verified Load → Validate → Query — a SHACL conformance gate.
- hub Ingest → Carve → Reason — scale meets hardware, for sources larger than one backend.
Build your own
- Building a chain — the method: design backwards from the output, make the scaling decision, map verbs to UDFs. Includes the shape vocabulary (head · waist · tail) for talking about which step you're on.
- Choosing a process — the decision table from goal × scale to a pattern.
See also
- query_stats Scale & benchmarks — the parallel-ingest ceiling these chains build on.
- rocket_launch Roadmap — the carve / re-encode / park-graph lifecycle landing across v0.6.n.
- layers_clear The four pillars — the engines the verbs map onto.