Www.w3.org/2010/11/TPAC/RDF-SW-velocity.pdf. What Is The Semantic Web? (Infographic) Semantic Web Standards. RDF/XML Syntax Specification (Revised) Status of This Document This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at This document is an edited version of the 2004 RDF XML Syntax Specification Recommendation.
The purpose of this revision is to make this document available as part of the RDF 1.1 document set. Changes are limited to revised references, terminology updates, and adaptations to the introduction. The technical content of the document is unchanged, except for the fact that the datatype XMLLiiteral is marked as non-normative in RDF 1.1. This document was published by the RDF Working Group as a Recommendation. This document has been reviewed by W3C Members, by software developers, and by other W3C groups and interested parties, and is endorsed by the Director as a W3C Recommendation. 2. 6. Quick Intro to RDF. Quick Intro to RDF This is a really brief introduction to Resource Description Framework (RDF).
You might also be interested in... For a more detailed look at RDF, see RDF in Depth on this site, which this page was based on. Two video introductions to the Semantic Web and RDF and RDFa by Manu Sporny are very good. Ian Davis's RDF Tutorial slides are also very good. There is also a Russian translation of this page. RDF is a method for expressing knowledge in a decentralized world and is the foundation of the Semantic Web, in which computer applications make use of distributed, structured information spread throughout the Web. The Big Picture RDF is a general method to decompose any type of knowledge into small pieces, with some rules about the semantics, or meaning, of those pieces. @prefix : < . The meaning is obvious. If you know XML, here's a brief comparison. But you don't have to use XML.
Consider this second document of RDF: So why use RDF? RDF Defined Conclusion. How RDF Databases Differ from Other NoSQL Solutions - The Datagraph Blog. This started out as an answer at Semantic Overflow on how RDF database systems differ from other currently available NoSQL solutions. I've here expanded the answer somewhat and added some general-audience context. RDF database systems are the only standardized NoSQL solutions available at the moment, being built on a simple, uniform data model and a powerful, declarative query language.
These systems offer data portability and toolchain interoperability among the dozens of competing implementations that are available at present, avoiding any need to bet the farm on a particular product or vendor. In case you're not familiar with the term, NoSQL ("Not only SQL") is a loosely-defined umbrella moniker for describing the new generation of non-relational database systems that have sprung up in the last several years. These systems tend to be inherently distributed, schema-less, and horizontally scalable. RDF database systems form the largest subset of this last NoSQL category. OpenLink Virtuoso - RDF Views. Demo.demo.Orders: Northwind RDF View Definition prefix northwind: < ... create iri class northwind:Order < (in order_id integer not null) . ... alter quad storage virtrdf:DefaultQuadStorage ... from Demo.demo.Customers as customers from Demo.demo.Orders as orders ... { create virtrdf:NorthwindDemo as graph iri (" { ... northwind:Order (orders.OrderID) a northwind:Order as virtrdf:Order-Order ; northwind:orderDate orders.OrderDate as virtrdf:Order-order_date ; northwind:requiredDate orders.RequiredDate as virtrdf:Order-required_date ; ... northwind:has_customer northwind:Customer (orders.CustomerID) as virtrdf:Order-order_has_customer northwind:has_employee northwind:Employee (orders.EmployeeID) as virtrdf:Order-order_has_employee ; ... } }
FOAF Vocabulary Specification. Classes Class: foaf:Agent Agent - An agent (eg. person, group, software or physical artifact). The Agent class is the class of agents; things that do stuff. A well known sub-class is Person, representing people. Other kinds of agents include Organization and Group. The Agent class is useful in a few places in FOAF where Person would have been overly specific. [#] [back to top] Class: foaf:Document Document - A document. The Document class represents those things which are, broadly conceived, 'documents'. The Image class is a sub-class of Document, since all images are documents. We do not (currently) distinguish precisely between physical and electronic documents, or between copies of a work and the abstraction those copies embody. [#] [back to top] Class: foaf:Group Group - A class of Agents.
The Group class represents a collection of individual agents (and may itself play the role of a Agent, ie. something that can perform actions). Here is an example. <! [#] [back to top] Class: foaf:Image. C Semantic Web FAQ. The term “rules” in the context of the Semantic Web refers to elements of logic programming and rule based systems bound to Semantic Web data. Rules offer a way to express, for example, constraints on the relationships defined by by RDF, or may be used to discover new, implicit relationships. Various rule systems (production rules, Prolog-like systems, etc) are very different from one another, and it is not possible to define one rule language to encompass them all. However, it is possible to define a “core” that is essentially understood by all rule systems. This core is based on restricted kind of rule, called a “Horn” rule, which (like most rules) has the form “if conditions then consequence”, but it places certain restrictions on the kinds of conditions and consequences that can be used.
A general example may help. While integrating data coming from different sources, the data may include references to persons, their name, homepage, email addresses, etc.