Querying with SPARQL

SPARQL is to a graph what SQL is to tables. If you can write a SELECT with joins, you can write SPARQL. The shape is SELECT ?vars WHERE { pattern }, where the pattern is a set of subject–predicate–object triples that share variables.

Where to Run Queries

Surface	Endpoint	Access
SPARQL Playground (`/governance/sparql`)	`GET \| POST /api/v1/rdf/sparql`	Admin
Ontology Studio → Query, glossary selected	`POST /api/v1/glossaries/{id}/sparql`	`ViewAll` on that glossary
Ontology Studio → Query, All glossaries	`GET \| POST /api/v1/rdf/sparql`	Admin
MCP `sparql_query` tool	Same as above	Admin principal (not bots)

Glossary-scoped SPARQL runs against the database-primary glossary model, it works with RDF storage off, and cannot reach other assets, external datasets, or SERVICE endpoints. Catalog-wide SPARQL runs against the triple store and is admin-only.

Named Graphs

Always scope instance-data queries to the knowledge graph. Ontology and shapes triples live elsewhere, so an unscoped ?s ?p ?o returns schema noise.

Graph	Contents
`https://open-metadata.org/graph/knowledge`	Instance data, every entity and relationship.
`https://open-metadata.org/graph/ontology`	The `om:` ontology.
`https://open-metadata.org/graph/shapes`	SHACL shapes.
`https://open-metadata.org/graph/metadata`	Dataset bookkeeping.
`https://open-metadata.org/graph/inferred/{rule}`	One graph per materialized inference rule.

Prefixes

The console pre-populates these; include them in API calls yourself.

PREFIX om:    <https://open-metadata.org/ontology/>
PREFIX dcat:  <http://www.w3.org/ns/dcat#>
PREFIX dct:   <http://purl.org/dc/terms/>
PREFIX prov:  <http://www.w3.org/ns/prov#>
PREFIX skos:  <http://www.w3.org/2004/02/skos/core#>
PREFIX foaf:  <http://xmlns.com/foaf/0.1/>
PREFIX rdfs:  <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd:   <http://www.w3.org/2001/XMLSchema#>
PREFIX dqv:   <http://www.w3.org/ns/dqv#>

The Vocabulary You Will Use Most

Entity IRIs follow https://open-metadata.org/entity/{entityType}/{uuid}.

Predicate	Meaning
`om:fullyQualifiedName`, `om:description`, `om:name`	Core literals present on every entity.
`om:belongsToService`, `om:belongsToDatabase`, `om:belongsToSchema`	Containment upward.
`om:hasColumn`	Table → column.
`om:hasTag`	Entity → classification tag.
`om:hasGlossaryTerm`	Entity → glossary term (concept).
`om:hasTier`	Entity → tier tag.
`om:hasOwner`, `prov:wasAttributedTo`	Ownership.
`om:belongsToDomain`, `om:hasDataProduct`	Domain and data-product membership.
`prov:wasDerivedFrom`	Lineage: downstream `wasDerivedFrom` upstream.
`prov:wasInfluencedBy`	The `downstream` relationship direction.
`om:UPSTREAM`	The `om:` namespace’s own lineage predicate, written alongside `prov:wasDerivedFrom`. Uppercase, deliberately: this is the exact form stored in the graph.
`om:hasLineageDetails`, `om:hasColumnLineage`, `om:fromColumn`, `om:toColumn`	Column-level lineage detail.
`om:testedBy`	Entity → test case.
`skos:broader`, `skos:narrower`, `skos:exactMatch`	Concept hierarchy and equivalence.
`om:relatedTo`, `om:partOf`, `om:hasPart`, `om:calculatedFrom`, `om:usedToCalculate`, `om:antonym`	Typed concept relations.

Discover the schema instead of guessing it. GET /api/v1/rdf/ontology returns the full ontology; the MCP tool ontology_describe does the same for agents and accepts a resource URI for a focused DESCRIBE. Reading the actual class and property declarations beats guessing predicate names, for you and for an LLM.

Limits

Every read runs behind an admission guard:

Limit	Value
Default / maximum result rows	1,000 / 10,000
Maximum query length	100,000 characters
Maximum output	10 MB
Query timeout	30 s
Global / per-principal concurrency	8 / 2

Writes (INSERT, DELETE, DROP, LOAD, CLEAR, CREATE) are rejected on the read endpoints. POST /api/v1/rdf/sparql/update exists for admins, but see the warning below. Federation (SERVICE clauses to external endpoints) is disabled by default. When enabled, target URIs must appear verbatim in an allowlist, trailing slashes matter.

Do not use SPARQL UPDATE to change your catalog. The graph is a derived index; the next reindex discards anything written directly. Write through the entity APIs.

Cookbook

Discovery

# What classes exist in the graph, and how many of each?
PREFIX om: <https://open-metadata.org/ontology/>
SELECT ?type (COUNT(?s) AS ?count) WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> { ?s a ?type }
}
GROUP BY ?type
ORDER BY DESC(?count)

# Everything asserted about one entity
DESCRIBE <https://open-metadata.org/entity/table/8d9b1a34-0f11-4c2e-9b1a-6f2d1c4e7a90>

Governance

# Every table carrying a PII tag, with its service
PREFIX om: <https://open-metadata.org/ontology/>
SELECT ?fqn ?tag ?service WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?t a om:Table ;
       om:fullyQualifiedName ?fqn ;
       om:hasTag ?tag .
    OPTIONAL { ?t om:belongsToService ?service }
    FILTER(CONTAINS(STR(?tag), "PII"))
  }
}
ORDER BY ?fqn
LIMIT 200

# Tier-1 tables with no owner — the governance backlog, in one query
PREFIX om: <https://open-metadata.org/ontology/>
SELECT ?fqn WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?t a om:Table ;
       om:fullyQualifiedName ?fqn ;
       om:hasTier ?tier .
    FILTER(CONTAINS(STR(?tier), "Tier1"))
    FILTER NOT EXISTS { ?t om:hasOwner ?o }
  }
}

# Coverage gap: tables with no glossary term at all
PREFIX om: <https://open-metadata.org/ontology/>
SELECT ?fqn WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?t a om:Table ; om:fullyQualifiedName ?fqn .
    FILTER NOT EXISTS { ?t om:hasGlossaryTerm ?term }
  }
}
LIMIT 500

Lineage

# All upstream tables of one dashboard, at any depth
PREFIX om:   <https://open-metadata.org/ontology/>
PREFIX prov: <http://www.w3.org/ns/prov#>
SELECT DISTINCT ?upstreamFqn WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    <https://open-metadata.org/entity/dashboard/{uuid}> prov:wasDerivedFrom+ ?u .
    ?u a om:Table ; om:fullyQualifiedName ?upstreamFqn .
  }
}

# Blast radius: everything downstream of one column
PREFIX om:   <https://open-metadata.org/ontology/>
PREFIX prov: <http://www.w3.org/ns/prov#>
SELECT DISTINCT ?downstream ?type WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?d prov:wasDerivedFrom+ <https://open-metadata.org/entity/column/{uuid}> .
    ?d om:fullyQualifiedName ?downstream ; a ?type .
  }
}

prov:wasDerivedFrom+ is a property path, SPARQL’s transitive traversal operator. It is the single feature that makes graph queries worth the switch, and it has no clean SQL equivalent. If you enable the transitive lineage closure inference rule, the closure is materialized and you can drop the +.

The Ontology, Applied

# Every asset realizing a concept and its narrower concepts
PREFIX om:   <https://open-metadata.org/ontology/>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
SELECT ?assetFqn ?conceptFqn WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?concept skos:broader* <https://open-metadata.org/entity/glossaryTerm/{uuid}> ;
             om:fullyQualifiedName ?conceptFqn .
    ?asset om:hasGlossaryTerm ?concept ;
           om:fullyQualifiedName ?assetFqn .
  }
}

# Concepts modeled but never realized — ontology debt
PREFIX om: <https://open-metadata.org/ontology/>
SELECT ?conceptFqn WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?c a om:GlossaryTerm ; om:fullyQualifiedName ?conceptFqn .
    FILTER NOT EXISTS { ?asset om:hasGlossaryTerm ?c }
  }
}
ORDER BY ?conceptFqn

# Two assets that share a business concept but have no technical lineage
PREFIX om:   <https://open-metadata.org/ontology/>
PREFIX prov: <http://www.w3.org/ns/prov#>
SELECT DISTINCT ?a ?b ?conceptFqn WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?x om:hasGlossaryTerm ?c ; om:fullyQualifiedName ?a .
    ?y om:hasGlossaryTerm ?c ; om:fullyQualifiedName ?b .
    ?c om:fullyQualifiedName ?conceptFqn .
    FILTER(STR(?a) < STR(?b))
    FILTER NOT EXISTS { ?x prov:wasDerivedFrom ?y }
    FILTER NOT EXISTS { ?y prov:wasDerivedFrom ?x }
  }
}
LIMIT 100

Structure

# Foreign-key style references between columns
PREFIX om: <https://open-metadata.org/ontology/>
SELECT ?fromCol ?toCol WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?details om:fromColumn ?f ; om:toColumn ?t .
    ?f om:fullyQualifiedName ?fromCol .
    ?t om:fullyQualifiedName ?toCol .
  }
}
LIMIT 200

# Assets owned by a team, grouped by type
PREFIX om: <https://open-metadata.org/ontology/>
SELECT ?type (COUNT(?asset) AS ?count) WHERE {
  GRAPH <https://open-metadata.org/graph/knowledge> {
    ?asset om:hasOwner ?team ; a ?type .
    ?team om:fullyQualifiedName "Data Platform" .
  }
}
GROUP BY ?type
ORDER BY DESC(?count)

Calling the API

# POST (preferred for anything non-trivial)
curl -X POST "$COLLATE_HOST/api/v1/rdf/sparql" \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"query":"SELECT ?s ?p ?o WHERE { GRAPH <https://open-metadata.org/graph/knowledge> { ?s ?p ?o } } LIMIT 10"}'

# GET with format and inference
curl -G "$COLLATE_HOST/api/v1/rdf/sparql" \
  -H "Authorization: Bearer $TOKEN" \
  --data-urlencode 'query=SELECT ?s WHERE { ?s a <https://open-metadata.org/ontology/Table> } LIMIT 5' \
  --data-urlencode 'format=csv' \
  --data-urlencode 'inference=none'

Result formats: json (default), xml, csv, tsv for SELECT/ASK; turtle, jsonld, ntriples, rdfxml for CONSTRUCT/DESCRIBE.

Performance Notes

Always scope to the named graph. Unscoped patterns scan schema and shapes as well.
LIMIT early. The guard truncates you at 1,000 rows by default anyway; be explicit.
Bind the most selective triple first. Start from a specific IRI or an indexed literal like om:fullyQualifiedName, not from ?s a om:Table.
Property paths are powerful and expensive. + and * over a large lineage graph can hit the 30-second timeout. If you run one regularly, materialize it as an inference rule instead.
Prefer FILTER NOT EXISTS over OPTIONAL + !BOUND. Same result, better plan.

Reasoning & Validation

Materialize the closures you keep re-computing.

Graph Insights

Pre-computed importance, communities, and paths.

Ontology & Knowledge Graph

Querying the Knowledge Graph with SPARQL | Collate

Querying with SPARQL

Where to Run Queries

Named Graphs

Prefixes

The Vocabulary You Will Use Most

Limits

Cookbook

Discovery

Governance

Lineage

The Ontology, Applied

Structure

Calling the API

Performance Notes

Next

Reasoning & Validation

Graph Insights

​Querying with SPARQL

​Where to Run Queries

​Named Graphs

​Prefixes

​The Vocabulary You Will Use Most

​Limits

​Cookbook

​Discovery

​Governance

​Lineage

​The Ontology, Applied

​Structure

​Calling the API

​Performance Notes

​Next

Reasoning & Validation

Graph Insights

Querying with SPARQL

Where to Run Queries

Named Graphs

Prefixes

The Vocabulary You Will Use Most

Limits

Cookbook

Discovery

Governance

Lineage

The Ontology, Applied

Structure

Calling the API

Performance Notes

Next