Reference
Reference materials for Fluree developers and operators.
Reference Guides
Glossary
Definitions of key terms and concepts:
- RDF terminology
- Fluree-specific terms
- Database concepts
- Query terminology
- Index terminology
Fluree System Vocabulary
Complete reference for Fluree's system vocabulary under https://ns.flur.ee/db#:
- Commit metadata predicates (
f:t,f:address,f:time,f:previous, etc.) - Search query vocabulary (BM25 and vector search patterns)
- Nameservice record fields and type taxonomy
- Policy vocabulary
- Namespace codes
Standards and Feature Flags
Standards and feature-flag reference:
- SPARQL 1.1 compliance
- JSON-LD specifications
- W3C standards support
- Feature flags
- Experimental features
- Deprecated features
Graph Identities and Naming
Naming conventions for graphs, ledgers, and identifiers:
- User-facing terminology (ledger, graph IRI, graph source, graph snapshot)
- Time pinning syntax (
@t:,@iso:,@commit:) - Named graphs within a ledger
- Base resolution for graph references
Crate Map
Overview of Fluree's Rust crate architecture:
- Core crates
- API crates
- Query engine crates
- Storage crates
- Dependency relationships
Quick Reference
Common Namespaces
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix schema: <http://schema.org/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix dc: <http://purl.org/dc/terms/> .
Fluree Namespaces
@prefix f: <https://ns.flur.ee/db#> .
Time Specifiers
ledger:branch@t:123 # Transaction number
ledger:branch@iso:2024-01-22 # ISO timestamp
ledger:branch@commit:bafybeig... # Commit ContentId
HTTP Status Codes
| Code | Meaning | Common Cause |
|---|---|---|
| 200 | OK | Success |
| 400 | Bad Request | Invalid syntax |
| 401 | Unauthorized | Missing auth |
| 403 | Forbidden | Policy denied |
| 404 | Not Found | Ledger not found |
| 408 | Timeout | Query too slow |
| 413 | Payload Too Large | Request too big |
| 429 | Too Many Requests | Rate limited |
| 500 | Internal Error | Server error |
| 503 | Unavailable | Overloaded |
Index Types
| Index | Order | Optimized For |
|---|---|---|
| SPOT | Subject-Predicate-Object-Time | Entity properties |
| POST | Predicate-Object-Subject-Time | Property values |
| OPST | Object-Predicate-Subject-Time | Value lookups |
| PSOT | Predicate-Subject-Object-Time | Predicate scans |
Standards Compliance
RDF Standards
- RDF 1.1: Full compliance
- Turtle: Full support
- JSON-LD 1.1: Full compliance
- N-Triples: Support (future)
Query Standards
- SPARQL 1.1 Query: Full compliance
- SPARQL 1.1 Update: Partial support
- GeoSPARQL: Planned
Security Standards
- JWS (RFC 7515): Full support
- JWT (RFC 7519): Full support
- Verifiable Credentials: W3C compliant
- DIDs: did:key, did:web support
Performance Benchmarks
Typical performance characteristics:
Query Performance
| Query Type | Small DB | Medium DB | Large DB |
|---|---|---|---|
| Simple lookup | < 1ms | < 5ms | < 10ms |
| Pattern match | < 10ms | < 50ms | < 100ms |
| Complex join | < 50ms | < 200ms | < 500ms |
| Aggregation | < 100ms | < 500ms | < 2s |
Transaction Performance
| Operation | Typical Time |
|---|---|
| Small insert (< 10 triples) | < 10ms |
| Medium insert (< 100 triples) | < 50ms |
| Large insert (< 1000 triples) | < 200ms |
| Update | < 20ms |
| Upsert | < 30ms |
Indexing Performance
| Workload | Rate |
|---|---|
| Light | 1,000 flakes/sec |
| Medium | 5,000 flakes/sec |
| Heavy | 10,000 flakes/sec |
Related Documentation
- Glossary - Term definitions
- Compatibility - Standards compliance
- Crate Map - Code architecture