Isolation Levels

Read Committed

GraphDB supports the read committed isolation level, where an update is only visible to other users when it has been committed.

Stored Procedures

Supported

GraphDB supports rulesets that are stored as .pie files and can be compiled and instantiated.

System Architecture

Shared-Memory

All nodes in the GraphDB cluster have a shared knowledge of data structures such as the global page cache.

Query Compilation

Code Generation Stored Procedure Compilation

GraphDB allows users to define custom rulesets, which can be compiled using its internal rule compiler. The rulesets are used to generate java code and are then instantiated.

Storage Architecture

Disk-oriented

GraphDB supports a disk-oriented storage architecture, where all of the data is stored in disk files.

Views

Virtual Views

GraphDB supports a Graph View interface which takes in SPARQL queries and retrieves data for the user, which is also visually shown.

Indexes

Hash Table

GraphDB supports indexes that are implemented with hash tables. The GeoSPARQL plugin for GraphDB , which is used for geo-spatial data representation and querying, supports the quad prefix tree and geohash prefix tree for indexing.

Data Model

Triplestore / RDF

Query Interface

SPARQL

GraphDB supports SPARQL for RDF queries.