A triplestore or RDF store is a purpose-built
database
In computing, a database is an organized collection of data or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and a ...
for the storage and retrieval of
triples through
semantic queries. A triple is a data entity composed of
subject–
predicate–
object, like "Bob is 35" (i.e., Bob's age measured in years is 35) or "Bob knows Fred".
Much like a
relational database
A relational database (RDB) is a database based on the relational model of data, as proposed by E. F. Codd in 1970.
A Relational Database Management System (RDBMS) is a type of database management system that stores data in a structured for ...
, information in a triplestore is stored and retrieved via a
query language. Unlike a relational database, a triplestore is optimized for the storage and retrieval of triples. In addition to queries, triples can usually be imported and exported using the
Resource Description Framework
The Resource Description Framework (RDF) is a method to describe and exchange graph data. It was originally designed as a data model for metadata by the World Wide Web Consortium (W3C). It provides a variety of syntax notations and formats, of whi ...
(RDF) and other formats.
Implementations
Some triplestores have been built as database engines from scratch, while others have been built on top of existing commercial relational database engines (such as
SQL-based) or NoSQL
document-oriented database
A document-oriented database, or document store, is a computer program and data storage system designed for storing, retrieving and managing document-oriented information, also known as semi-structured data.
Document-oriented databases are one ...
engines. Like the early development of
online analytical processing
In computing, online analytical processing (OLAP) (), is an approach to quickly answer multi-dimensional analytical (MDA) queries. The term ''OLAP'' was created as a slight modification of the traditional database term online transaction proces ...
(OLAP) databases, this intermediate approach allowed large and powerful database engines to be constructed for little programming effort in the initial phases of triplestore development. A difficulty with implementing triplestores over SQL is that although "triples" may thus be "stored", implementing efficient querying of a graph-based RDF model (such as mapping from
SPARQL) onto SQL queries is difficult.
Related database types
Adding a name to the triple makes a "quad store" or
named graph.
A
graph database has a more generalized structure than a triplestore, using graph structures with nodes, edges, and properties to represent and store data. Graph databases might provide index-free adjacency, meaning every element contains a direct pointer to its adjacent elements, and no index lookups are necessary. General graph databases that can store any graph are distinct from specialized graph databases such as triplestores and
network databases.
See also
*
Dataspaces
*
Entity–relationship model
* – The first two elements of the ''class-attribute-value'' triple (class, attribute) are pieces of some structural metadata having a defined semantic. The third element is a value, preferably from some controlled vocabulary.
*
Outline of databases
*
Semantic Integration
*
Semantic MediaWiki — an example of subject-predicate-object support for
wikis
A wiki ( ) is a form of hypertext publication on the internet which is collaboratively edited and managed by its audience directly through a web browser. A typical wiki contains multiple pages that can either be edited by the public or l ...
, advanced query support, and implementations by many large organizations
*
SPARQL – W3C specification involving subject-predicate-object triples
**
List of SPARQL implementations
*
Entity–attribute–value model is a similar approach to data modeling.
References
External links
A list of large triplestoresLehigh University Benchmark (LUBM)How RDF Databases Differ from Other NoSQL SolutionsW3C SPARQL Working Groupwas RDF Data Access Working Group
SPARQL Query languageSPARQL ProtocolSPARQL 1.1 UpdateW3C Recommendation 21 March 2013
{{Use dmy dates, date=March 2017
Types of databases
Database management systems
Database theory
Metadata
Semantic Web