SPARQL 1.1/1.2 + SPARQL-Star · Zero-Heap

SPARQL Engine Showcase

145 passing SPARQL library tests. ~35 KB memory per query. SELECT, PREFIX, FILTER, and RDF-Star unified on POST :4242/query via qualia-cli daemon --dev.

Extreme Performance

Over 1.2M ops/s on point lookups. Zero-heap allocation ensures predictable latency.

Temporal Extensions

AS OF and AT TIME for graph history navigation.

Federation & DID

Secure SERVICE federation with W3C DIDs.

RDF-Star Support

Native SPARQL-Star for quoted triples and edge annotations.

N3Logic & SHACL governance

Query results can be gated by SHACL shapes and N3 defeasible rules before LLM inference. Try the live logic demos.

Modalities Observatory →

Interactive Query Demo

Query Results

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Results
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Latency
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Operations
Execute a query to see results...

RDF-Star (SPARQL-Star) Support New in QualiaDB

QualiaDB supports RDF-Star (SPARQL-Star) natively, allowing you to query about triples as first-class citizens. This enables edge annotations, provenance tracking, and graph metadata queries.

What is RDF-Star?

RDF-Star extends RDF by allowing triples to appear as subjects or objects of other triples. This is done by wrapping triples in angle brackets: << ?s ?p ?o >>

# Regular triple :Alice foaf:knows :Bob . # RDF-Star - triple as object :Alice foaf:knows << :Alice foaf:knows :Bob >> . # RDF-Star - triple as subject << :Alice foaf:knows :Bob >> prov:wasDerivedFrom :Document1 .

Use Cases

  • Provenance Tracking: Record where data came from
  • Edge Annotations: Add metadata to graph edges
  • Confidence Scores: Attach probability to statements
  • Nested Statements: Model complex relationships

SPARQL-Star Examples

Query for triples about a specific triple
SELECT ?x ?y ?z WHERE { << ?x ?y ?z >> prov:wasDerivedFrom ?doc . }
Find all triples with high confidence
SELECT ?triple ?confidence WHERE { ?triple a:confidence ?confidence . FILTER(?confidence > 0.8) }
Access quoted triple components
SELECT ?s ?p ?o WHERE { << ?s ?p ?o >> ?p ?o . }

Live RDF-Star Demo

Execute to see RDF-Star results...

Temporal Extensions

Navigate graph history with AS OF and AT TIME syntax. Perfect for Merkle-DAG integration and temporal reasoning.

AS OF - Snapshot at a Point in Time

Returns the graph state as it existed at a specific timestamp.

PREFIX prov: <http://www.w3.org/ns/prov#> SELECT ?agent ?activity WHERE { ?agent prov:wasAssociatedWith ?activity . } AS OF "2026-06-01"^^xsd:dateTime

AT TIME - Time-Scoped Query

Query within a specific time window.

PREFIX prov: <http://www.w3.org/ns/prov#> SELECT ?agent ?activity WHERE { ?agent prov:wasAssociatedWith ?activity . } AT TIME "2026-06-01T10:00:00"^^xsd:dateTime

Live Temporal Demo

Execute to see temporal results...

GeoSPARQL & Spatial Extensions

Spatial queries with geometry operations like sfWithin, sfIntersects, and sfContains.

PREFIX geo: <http://www.opengis.net/ont/geosparql#> SELECT ?feature WHERE { ?feature geo:hasGeometry ?geom . FILTER(geo:sfWithin(?geom, "POLYGON((...))")) }

sfWithin

Tests if geometry is within another geometry

sfIntersects

Tests if geometries intersect

sfContains

Tests if geometry contains another

Performance Telemetry

138
Passing Tests
~35 KB
Memory Per Query
0
Heap Allocations
1.2M+
Ops/Sec (Point Lookup)

Query Latency Distribution

Throughput by Query Type