1. Using Graph Studio in Oracle Autonomous Database
  2. Introduction to Graph Data in Autonomous Database
  3. Key Terms and Concepts for Working with Graphs

Key Terms and Concepts for Working with Graphs

This section briefly explains the key concepts of graphs and other graph features. These may be helpful when working with the interactive Graph Studio available in Autonomous Database.

Graph Studio

Graph Studio is a user interface available with Oracle Autonomous Database that provides access to all available graph features. You can:
  • Create property graphs, execute PGQL queries, graph visualizations, and perform analytics.
  • Create RDF graphs, execute SPARQL queries and perform graph visualizations.

Property Graph

A property graph consists of vertices that are linked together by edges. Both vertices and edges can have a set of properties attached to them. Common properties are id and label. The label property often identifies what the vertex or edge represent. For example, a vertex representing a bank account may have the label Account, while an edge representing a transfer of funds between accounts may have the label Transfer.

A property graph is the main data structure used with Graph Studio.

Property Graph Wizard

The property graph wizard in Graph Studio guides you through the steps to easily create a property graph from existing relational database tables.

This graph creation workflow comprises the following steps:

  1. Overview: Provide the graph name and description.
  2. Select Tables: Select the input tables.
  3. Define Graph: View the graph definition and iteratively refine the mappings.
  4. Summary: View the property graph summary and create the graph for analysis and visualization.

RDF

RDF (Resource Description Framework) is a W3C-standard data model for representing linked data. RDF uses Uniform Resource Identifiers (URIs) as globally-unique identifiers for resources and also uses URIs to identify the type of relationship between two resources. In addition to URIs, RDF uses literals to represent scalar values such as numbers, strings and timestamps.

RDF Graph

RDF models linked data as a directed, labeled RDF graph, where each edge is usually called a triple. The source vertex of the edge is called the subject of the triple. The label or name of the edge is called the predicate of the triple, and the destination vertex of the edge is called the object of the triple.

RDF Graph Collection

An RDF graph collection is an RDF graph that contains all triples from a collection of individual RDF graphs. The collection can also include entailed triples inferred by applying rules and ontologies to the graph collection.

Rule, Rulebase, and Inferencing

A rule is an object that can be applied to draw inferences from semantic data.

A rulebase is an object that contains rules.

Inferencing is the ability to make logical deductions based on rules.

Entailment

An entailment (rules index) is an object containing precomputed triples that can be inferred from applying a specified set of rule bases to a specified set of RDF graphs.

RDF N-Triple Format

N-Triple (.nt) is one of the common RDF data formats. Each statement in the file represents a triple:{subject or resource, predicate or property, object or value}.

RDF N-Quad Format

N-Quad (.nq) is another popular RDF data format. This format allows both regular triples and extended triples. An extended triple is made up of four components: {subject or resource, predicate or property, object or value, graph name}. The graph name component of an RDF triple must either be null or a URI.

RDF Wizard

The RDF wizard utility in Graph Studio guides you on the steps to create an RDF graph or RDF graph collection.

PGQL Graph Queries

PGQL (Property Graph Query Language) is a graph pattern-matching query language for property graphs. PGQL combines graph pattern matching with familiar constructs from SQL, such as SELECT, FROM, and WHERE. See Property Graph Query Language (PGQL) for more information on PGQL specifications.

SPARQL Queries

SPARQL Protocol and RDF Query Language (SPARQL) is one of the technologies standardized by the W3C for querying RDF data. See the W3C SPARQL 1.1 standard for more information.

Graph Algorithm

A graph algorithm is a pre-packaged set of instructions to traverse or analyze a graph. For example, you can find a shortest path or important vertices in your graph. PageRank is a well known graph algorithm, which ranks the importance of vertices. Graph Studio notebooks expose over 60 such algorithms as built-in functions.

Notebooks

Notebooks are interactive browser-based applications that enable data engineers, analysts, and scientists to be more productive by developing, organizing, executing, and sharing code, and by visualizing results without using the command line or needing to install anything. Notebooks enable you to execute code, to work interactively with long workflows, and to collaborate on projects.

In addition to code execution, notebooks support a large set of built-in visualization capabilities.

Job

A job is a potentially long-running asynchronous operation in Graph Studio. An example of a job is loading a graph into memory or creating a graph from tables.