Kingsley Idehen's Blog Data Space

Simple Virtuoso Installation & Utilization Guide for SPARQL Users (Update 5)

Sun, 16 Jan 2011 07:06:21 GMT

What is SPARQL?

A declarative query language from the W3C for querying structured propositional data (in the form of 3-tuple [triples] or 4-tuple [quads] records) stored in a deductive database (colloquially referred to as triple or quad stores in Semantic Web and Linked Data parlance).

SPARQL is inherently platform independent. Like SQL, the query language and the backend database engine are distinct. Database clients capture SPARQL queries which are then passed on to compliant backend databases.

Why is it important?

Like SQL for relational databases, it provides a powerful mechanism for accessing and joining data across one or more data partitions (named graphs identified by IRIs). The aforementioned capability also enables the construction of sophisticated Views, Reports (HTML or those produced in native form by desktop productivity tools), and data streams for other services.

Unlike SQL, SPARQL includes result serialization formats and an HTTP based wire protocol. Thus, the ubiquity and sophistication of HTTP is integral to SPARQL i.e., client side applications (user agents) only need to be able to perform an HTTP GET against a URL en route to exploiting the power of SPARQL.

How do I use it, generally?

Locate a SPARQL endpoint (DBpedia, LOD Cloud Cache, Data.Gov, URIBurner, others), or;
Install a SPARQL compliant database server (quad or triple store) on your desktop, workgroup server, data center, or cloud (e.g., Amazon EC2 AMI)
Start the database server
Execute SPARQL Queries via the SPARQL endpoint.

How do I use SPARQL with Virtuoso?

What follows is a very simple guide for using SPARQL against your own instance of Virtuoso:

Software Download and Installation
Data Loading from Data Sources exposed at Network Addresses (e.g. HTTP URLs) using very simple methods
Actual SPARQL query execution via SPARQL endpoint.

Installation Steps

Download Virtuoso Open Source or Virtuoso Commercial Editions
Run installer (if using Commercial edition of Windows Open Source Edition, otherwise follow build guide)
Follow post-installation guide and verify installation by typing in the command: virtuoso -? (if this fails check you've followed installation and setup steps, then verify environment variables have been set)
Start the Virtuoso server using the command: virtuoso-start.sh
Verify you have a connection to the Virtuoso Server via the command: isql localhost (assuming you're using default DB settings) or the command: isql localhost:1112 (assuming demo database) or goto your browser and type in: http://<virtuoso-server-host-name>:[port]/conductor (e.g. http://localhost:8889/conductor for default DB or http://localhost:8890/conductor if using Demo DB)
Go to SPARQL endpoint which is typically -- http://<virtuoso-server-host-name>:[port]/sparql
Run a quick sample query (since the database always has system data in place): select distinct * where {?s ?p ?o} limit 50 .

Troubleshooting

Ensure environment settings are set and functional -- if using Mac OS X or Windows, so you don't have to worry about this, just start and stop your Virtuoso server using native OS services applets
If using the Open Source Edition, follow the getting started guide -- it covers PATH and startup directory location re. starting and stopping Virtuoso servers.
Sponging (HTTP GETs against external Data Sources) within SPARQL queries is disabled by default. You can enable this feature by assigning "SPARQL_SPONGE" privileges to user "SPARQL". Note, more sophisticated security exists via WebID based ACLs.

Data Loading Steps

Identify an RDF based structured data source of interest -- a file that contains 3-tuple / triples available at an address on a public or private HTTP based network
Determine the Address (URL) of the RDF data source
Go to your Virtuoso SPARQL endpoint and type in the following SPARQL query: DEFINE GET:SOFT "replace" SELECT DISTINCT * FROM <RDFDataSourceURL> WHERE {?s ?p ?o}
All the triples in the RDF resource (data source accessed via URL) will be loaded into the Virtuoso Quad Store (using RDF Data Source URL as the internal quad store Named Graph IRI) as part of the SPARQL query processing pipeline.

Note: the data source URL doesn't even have to be RDF based -- which is where the Virtuoso Sponger Middleware comes into play (download and install the VAD installer package first) since it delivers the following features to Virtuoso's SPARQL engine:

Transformation of data from non RDF data sources (file content, hypermedia resources, web services output etc..) into RDF based 3-tuples (triples)
Cache Invalidation Scheme Construction -- thus, subsequent queries (without the define get:soft "replace" pragma will not be required bar when you forcefully want to override cache).
If you have very large data sources like DBpedia etc. from CKAN, simply use our bulk loader .

SPARQL Endpoint Discovery

Public SPARQL endpoints are emerging at an ever increasing rate. Thus, we've setup up a DNS lookup service that provides access to a large number of SPARQL endpoints. Of course, this doesn't cover all existing endpoints, so if our endpoint is missing please ping me.

Here are a collection of commands for using DNS-SD to discover SPARQL endpoints:

dns-sd -B _sparql._tcp sparql.openlinksw.com -- browse for services instances
dns-sd -Z _sparql._tcp sparql.openlinksw.com -- output results in Zone File format

Using HTTP from Ruby -- you can just make SPARQL Protocol URLs re. SPARQL
Using SPARQL Endpoints via Ruby -- Ruby example using DBpedia endpoint
Interactive SPARQL Query By Example (QBE) tool -- provides a graphical user interface (as is common in SQL realm re. query building against RDBMS engines) that works with any SPARQL endpoint
Other methods of loading RDF data into Virtuoso
Virtuoso Sponger -- architecture and how it turns a wide variety of non RDF data sources into SPARQL accessible data
Using OpenLink Data Explorer (ODE) to populate Virtuoso -- locate a resource of interest; click on a bookmarklet or use context menus (if using ODE extensions for Firefox, Safari, or Chrome); and you'll have SPARQL accessible data automatically inserted into your Virtuoso instance.
W3C's SPARQLing Data Access Ingenuity -- an older generic SPARQL introduction post
Collection of SPARQL Query Examples -- GoodRelations (Product Offers), FOAF (Profiles), SIOC (Data Spaces -- Blogs, Wikis, Bookmarks, Feed Collections, Photo Galleries, Briefcase/DropBox, AddressBook, Calendars, Discussion Forums)
Collection of Live SPARQL Queries against LOD Cloud Cache -- simple and advanced queries.

Solving Real Problems by Leveraging Linked Data: Unambiguous & Verifiable Identity for HTTP Networks

Mon, 12 Jul 2010 03:25:03 GMT

Problem: Unambiguous Verifiable Network Identity.

How Does Linked Data Address This Problem? It provides critical infrastructure for the WebID Protocol that enables an innovative tweak of SSL/TLS.

What about OpenID? The WebID Protocol embraces and extends OpenID (in an open and positive way) via the WebID + OpenID Hybrid variant of the protocol -- basic effect is that OpenID calls are re-routed to the WebID aspect which simply removes Username and Password Authentication from the authentication challenge interaction pattern.

WebID Components

X.509 Certificate and Private Key Generator
Structured Profile Document (e.g. a FOAF based Profile) published to an HTTP Network (e.g. World Wide Web) and accessible at an Address (URL)
An Agent Identifier aka. WebID (an HTTP Name Reference re. URI variant) that's the Subject of a Structured Profile Document (actually a Descriptor Resource)
Mechanism for persisting Public Key data from X.509 Certificate to Structured Profile Document and associating it with Subject WebID (e.g. SPARUL or other HTTP based methods)
Mechanism for de-referencing Public Key data associated with a WebID (from its Structured Profile Document) for comparison against Public Key data following successful standard SSL/TLS protocol handshake (e.g. via SPARQL Query).

Demo

WebID + OpenID Hybrid Protocol Demo using ODS, Stackoverflow.com, and identi.ca. - YouTube Screencast Demo Part 1 using Firefox
WebID + OpenID Hybrid Protocol Demo using ODS, Stackoverflow.com, and identi.ca. - YouTube Screencast Demo Part 2 using Safari

Revisiting HTTP based Linked Data (Update 1 - Demo Video Links Added)

Thu, 04 Mar 2010 15:16:14 GMT

Motivation for this post arose from a series of Twitter exchanges between Tony Hirst and I, in relation to his blog post titled: So What Is It About Linked Data that Makes it Linked Dataâ¢ ?

At the end of the marathon session, it was clear to me that a blog post was required for future reference, at the very least :-)

What is Linked Data?

"Data Access by Reference" mechanism for Data Objects (or Entities) on HTTP networks. It enables you to Identify a Data Object and Access its structured Data Representation via a single Generic HTTP scheme based Identifier (HTTP URI). Data Object representation formats may vary; but in all cases, they are hypermedia oriented, fully structured, and negotiable within the context of a client-server message exchange.

Why is it Important?

Information makes the world tick!

Information doesn't exist without data to contextualize.

Information is inaccessible without a projection (presentation) medium.

All information (without exception, when produced by humans) is subjective. Thus, to truly maximize the innate heterogeneity of collective human intelligence, loose coupling of our information and associated data sources is imperative.

How is Linked Data Delivered?

Linked Data is exposed to HTTP networks (e.g. World Wide Web) via hypermedia resources bearing structured representations of data object descriptions. Remember, you have a single Identifier abstraction (generic HTTP URI) that embodies: Data Object Name and Data Representation Location (aka URL).

How are Linked Data Object Representations Structured?

A structured representation of data exists when an Entity (Datum), its Attributes, and its Attribute Values are clearly discernible. In the case of a Linked Data Object, structured descriptions take the form of a hypermedia based Entity-Attribute-Value (EAV) graph pictorial -- where each Entity, its Attributes, and its Attribute Values (optionally) are identified using Generic HTTP URIs.

Examples of structured data representation formats (content types) associated with Linked Data Objects include:

text/html
text/turtle
text/n3
application/json
application/rdf+xml
Others

How Do I Create Linked Data oriented Hypermedia Resources?

You markup resources by expressing distinct entity-attribute-value statements (basically these a 3-tuple records) using a variety of notations:

(X)HTML+RDFa,
JSON,
Turtle,
N3,
TriX,
TriG,
RDF/XML, and
Others (for instance you can use Atom data format extensions to model EAV graph as per OData initiative from Microsoft).

You can achieve this task using any of the following approaches:

Notepad
WYSIWYG Editor
Transformation of Database Records via Middleware
Transformation of XML based Web Services output via Middleware
Transformation of other Hypermedia Resources via Middleware
Transformation of non Hypermedia Resources via Middleware
Use a platform that delivers all of the above.

Practical Examples of Linked Data Objects Enable

Describe Who You Are, What You Offer, and What You Need via your structured profile, then leave your HTTP network to perform the REST (serendipitous discovery of relevant things)
Identify (via map overlay) all items of interest based on a 2km+ radious of my current location (this could include vendor offerings or services sought by existing or future customers)
Share the latest and greatest family photos with family members *only* without forcing them to signup for Yet Another Web 2.0 service or Social Network
No repetitive signup and username and password based login sequences per Web 2.0 or Mobile Application combo
Going beyond imprecise Keyword Search to the new frontier of Precision Find - Example, Find Data Objects associated with the keywords: Tiger, while enabling the seeker disambiguate across the "Who", "What", "Where", "When" dimensions (with negation capability)
Determine how two Data Objects are Connected - person to person, person to subject matter etc. (LinkedIn outside the walled garden)
Use any resource address (e.g blog or bookmark URL) as the conduit into a Data Object mesh that exposes all associated Entities and their social network relationships
Apply patterns (social dimensions) above to traditional enterprise data sources in combination (optionally) with external data without compromising security etc.

How Do OpenLink Software Products Enable Linked Data Exploitation?

Our data access middleware heritage (which spans 16+ years) has enabled us to assemble a rich portfolio of coherently integrated products that enable cost-effective evaluation and utilization of Linked Data, without writing a single line of code, or exposing you to the hidden, but extensive admin and configuration costs. Post installation, the benefits of Linked Data simply materialize (along the lines described above).

Our main Linked Data oriented products include:

OpenLink Data Explorer -- visualizes Linked Data or Linked Data transformed "on the fly" from hypermedia and non hypermedia data sources
URIBurner -- a "deceptively simple" solution that enables the generation of Linked Data "on the fly" from a broad collection of data sources and resource types
OpenLink Data Spaces -- a platform for enterprises and individuals that enhances distributed collaboration via Linked Data driven virtualization of data across its native and/or 3rd party content manager for: Blogs, Wikis, Shared Bookmarks, Discussion Forums, Social Networks etc
OpenLink Virtuoso -- a secure and high-performance native hybrid data server (Relational, RDF-Graph, Document models) that includes in-built Linked Data transformation middleware (aka. Sponger).

Hypertext Transfer Protocol 1.1 RFC
Open Data Protocol Glossary
Simple Explanation of RDF and Linked Data Dynamics
Collection of post from the past about Linked Data
Are We There Yet Re. Web++? -- includes link to podcast conversation with Jon Udell
Web of Linked Data Pivoting Demo from TED -- by Microsoft's Gary Flake
Microsoft Pivot atop Virtuoso Quad Store's Faceted Browser Engine-- My Demonstration of EAV model transcending data representation variations (i.e., RDF's EAV data model data served up in Microsoft CXML data representation format).

Linked Data & Socially Enhanced Collaboration (Enterprise or Individual) -- Update 1

Tue, 02 Mar 2010 20:47:54 GMT

Socially enhanced enterprise and invididual collaboration is becoming a focal point for a variety of solutions that offer erswhile distinct content managment features across the realms of Blogging, Wikis, Shared Bookmarks, Discussion Forums etc.. as part of an integrated platform suite. Recently, Socialtext has caught my attention courtesy of its nice features and benefits page . In addition, I've also found the Mike 2.0 portal immensely interesting and valuable, for those with an enterprise collaboration bent.

Anyway, Socialtext and Mike 2.0 (they aren't identical and juxtaposition isn't seeking to imply this) provide nice demonstrations of socially enhanced collaboration for individuals and/or enterprises is all about:

Identifying Yourself
Identifying Others (key contributors, peers, collaborators)
Serendipitous Discovery of key contributors, peers, and collaborators
Serendipitous Discovery by key contributors, peers, and collaborators
Develop and sustain relationships via socially enhanced professional network hybrid
Utilize your new "trusted network" (which you've personally indexed) when seeking help or propagating a meme.

As is typically the case in this emerging realm, the critical issue of discrete "identifiers" (record keys in sense) for data items, data containers, and data creators (individuals and groups) is overlooked albeit unintentionally.

How HTTP based Linked Data Addresses the Identifier Issue

Rather than using platform constrained identifiers such as:

email address (a "mailto" scheme identifier),
a dbms user account,
application specific account, or
OpenID.

It enables you to leverage the platform independence of HTTP scheme Identifiers (Generic URIs) such that Identifiers for:

You,
Your Peers,
Your Groups, and
Your Activity Generated Data,

simply become conduits into a mesh of HTTP -- referencable and accessible -- Linked Data Objects endowed with High SDQ (Serendipitious Discovery Quotient). For example my Personal WebID is all anyone needs to know if they want to explore:

My Profile (which includes references to data objects associated with my interests, social-network, calendar, bookmarks etc.)
Data generated by my activities across various data spaces (via data objects associated with my online accounts e.g. Del.icio.us, Twitter, Last.FM)
Linked Data Meshups via URIBurner (or any other Virtuoso instance) that provide an extend view of my profile

How FOAF+SSL adds Socially aware Security

Even when you reach a point of equilibrium where: your daily activities trigger orchestratestration of CRUD (Create, Read, Update, Delete) operations against Linked Data Objects within your socially enhanced collaboration network, you still have to deal with the thorny issues of security, that includes the following:

Single Sign On,
Authentication, and
Data Access Policies.

FOAF+SSL, an application of HTTP based Linked Data, enables you to enhance your Personal HTTP scheme based Identifer (or WebID) via the following steps (peformed by a FOAF+SSL compliant platform):

Imprint WebID within a self-signed x.509 based public key (certificate) associated with your private key (generated by FOAF+SSL platform or manually via OpenSSL)
Store public key components (modulous and exponent) into your FOAF based profile document which references your Personal HTTP Identifier as its primary topic
Leverage HTTP URL component of WebID for making public key components (modulous and exponent) available for x.509 certificate based authentication challenges posed by systems secured by FOAF+SSL (directly) or OpenID (indirectly via FOAF+SSL to OpenID proxy services).

Contrary to conventional experiences with all things PKI (Public Key Infrastructure) related, FOAF+SSL compliant platforms typically handle the PKI issues as part of the protocol implementation; thereby protecting you from any administrative tedium without compromising security.

Conclusions

Understanding how new technology innovations address long standing problems, or understanding how new solutions inadvertently fail to address old problems, provides time tested mechanisms for product selection and value proposition comprehension that ultimately save scarce resources such as time and money.

If you want to understand real world problem solution #1 with regards to HTTP based Linked Data look no further than the issues of secure, socially aware, and platform independent identifiers for data objects, that build bridges across erstwhile data silos.

If you want to cost-effectively experience what I've outlined in this post, take a look at OpenLink Data Spaces (ODS) which is a distributed collaboration engine (enterprise of individual) built around the Virtuoso database engines. It simply enhances existing collaboration tools via the following capabilities:

Addition of Social Dimensions via HTTP based Data Object Identifiers for all Data Items (if missing)

Ability to integrate across a myriad of Data Source Types rather than a select few across RDBM Engines, LDAP, Web Services, and various HTTP accessible Resources (Hypermedia or Non Hypermedia content types)
Addition of FOAF+SSL based authentication
Addition of FOAF+SSL based Access Control Lists (ACLs) for policy based data access.

Get Yourself A WebID in 5 Minutes or Less via OpenLink Data Spaces (an application layer built atop Virtuoso)
How To Share Resources Securely Using FOAF+SSL
FOAF+SSL & WebID Demonstration
OpenLink Data Spaces & Data Portability.

5 Game Changing Things about the OpenLink Virtuoso + AWS Cloud Combo

Sun, 31 Jan 2010 22:29:34 GMT

Here are 5 powerful benefits you can immediately derive from the combination of Virtuoso and Amazon's AWS services (specifically the EC2 and EBS components):

Acquire your own personal or service specific data space in the Cloud. Think DBase, Paradox, FoxPRO, Access of yore, but with the power of Oracle, Informix, Microsoft SQL Server etc.. using a Conceptual, as opposed to solely Logical, model based DBMS (i.e., a Hybrid DBMS Engine for: SQL, RDF, XML, and Full Text)
Ability to share and control access to your resources using innovations like FOAF+SSL, OpenID, and OAuth, all from one place
Construction of personal or organization based FOAF profiles in a matter of minutes; by simply creating a basic DBMS (or ODS application layer) account; and then using this profile to create strong links (references) to all your Data silos (esp. those from the Web 2.0 realm)
Load data sets from the LOD cloud or Sponge existing Web resources (i.e., on the fly data transformation to RDF model based Linked Data) and then use the combination to build powerful lookup services that enrich the value of URLs (think: Web addressable reports holding query results) that you publish
Bind all of the above to a domain that you own (e.g. a .Name domain) so that you have an attribution-friendly "authority" component for resource URLs and Entity URIs published from your Personal Linked Data Space on the Web (or private HTTP network).

In a nutshell, the AWS Cloud infrastructure simplifies the process of generating Federated presence on the Internet and/or World Wide Web. Remember, centralized networking models always end up creating data silos, in some context, ultimately! :-)

Introducing Virtuoso Universal Server (Cloud Edition) for Amazon EC2

Fri, 28 Nov 2008 19:27:12 GMT

What is it?

A pre-installed edition of Virtuoso for Amazon's EC2 Cloud platform.

What does it offer?

From a Web Entrepreneur perspective it offers:

Low cost entry point to a game-changing Web 3.0+ (and beyond) platform that combines SQL, RDF, XML, and Web Services functionality
Flexible variable cost model (courtesy of EC2 DevPay) tightly bound to revenue generated by your services
Delivers federated and/or centralized model flexibility for you SaaS based solutions
Simple entry point for developing and deploying sophisticated database driven applications (SQL or RDF Linked Data Web oriented)
Complete framework for exploiting OpenID, OAuth (including Role enhancements) that simplifies exploitation of these vital Identity and Data Access technologies
Easily implement RDF Linked Data based Mail, Blogging, Wikis, Bookmarks, Calendaring, Discussion Forums, Tagging, Social-Networking as Data Space (data containers) features of your application or service offering
Instant alleviation of challenges (e.g. service costs and agility) associated with Data Portability and Open Data Access across Web 2.0 data silos
LDAP integration for Intranet / Extranet style applications.

From the DBMS engine perspective it provides you with one or more pre-configured instances of Virtuoso that enable immediate exploitation of the following services:

RDF Database (a Quad Store with SPARQL & SPARUL Language & Protocol support)
SQL Database (with ODBC, JDBC, OLE-DB, ADO.NET, and XMLA driver access)
XML Database (XML Schema, XQuery/Xpath, XSLT, Full Text Indexing)
Full Text Indexing.

From a Middleware perspective it provides:

RDF Views (Wrappers / Semantic Covers) over SQL, XML, and other data sources accessible via SOAP or REST style Web Services
Sponger Service for converting non RDF information resources into RDF Linked Data "on the fly" via a large collection of pre-installed RDFizer Cartridges.

From the Web Server Platform perspective it provides an alternative to LAMP stack components such as MySQL and Apace by offering

HTTP Web Server
WebDAV Server
Web Application Server (includes PHP runtime hosting)
SOAP or REST style Web Services Deployment
RDF Linked Data Deployment
SPARQL (SPARQL Query Language) and SPARUL (SPARQL Update Language) endpoints
Virtuoso Hosted PHP packages for MediaWiki, Drupal, Wordpress, and phpBB3 (just install the relevant Virtuoso Distro. Package).

From the general System Administrator's perspective it provides:

Online Backups (Backup Set dispatched to S3 buckets, FTP, or HTTP/WebDAV server locations)
Synchronized Incremental Backups to Backup Set locations
Backup Restore from Backup Set location (without exiting to EC2 shell).

Higher level user oriented offerings include:

OpenLink Data Explorer front-end for exploring the burgeoning Linked Data Web
Ajax based SPARQL Query Builder (iSPARQL) that enables SPARQL Query construction by Example
Ajax based SQL Query Builder (QBE) that enables SQL Query construction by Example.

For Web 2.0 / 3.0 users, developers, and entrepreneurs it offers it includes Distributed Collaboration Tools & Social Media realm functionality courtesy of ODS that includes:

Point of presence on the Linked Data Web that meshes your Identity and your Data via URIs
System generated Social Network Profile & Contact Data via FOAF?
System generated SIOC (Semantically Interconnected Online Community) Data Space (that includes a Social Graph) exposing all your Web data in RDF Linked Data form
System generated OpenID and automatic integration with FOAF
Transparent Data Integration across Facebook, Digg, LinkedIn, FriendFeed, Twitter, and any other Web 2.0 data space equipped with RSS / Atom support and/or REST style Web Services
In-built support for SyncML which enables data synchronization with Mobile Phones.

How Do I Get Going with It?

Where Are All the RDF-based Semantic Web Applications?

Wed, 01 Oct 2008 23:09:00 GMT

In response to the "Semantic Web Technology" application classification scheme espoused by ReadWriteWeb (RWW), emphasized in the post titled: Where are all the RDF-based Semantic Web Apps?, here is my attempt to clarify and reintroduce what OpenLink Software offers (today) in relation to Semantic Web technology.

From the RWW Top-Down category, which I interpret as: technologies that produce RDF from non RDF data sources. Our product portfolio is comprised of the following; Virtuoso Universal Server, OpenLink Data Spaces, OpenLink Ajax Toolkit, and OpenLink Data Explorer (which includes ubiquity commands).

Virtuoso Universal Server functionality summary:

Generation of RDF Linked Data Views of SQL, XML, and Web Services in general
Deployment of RDF Linked Data
"On the Fly" generation of RDF Linked Data from Document Web information resources (i.e. distillation of entities from their containers e.g. Web pages) via Cartridges / Drivers
SPARQL query language support
SPARQL extensions that bring SPARQL closer to SQL e.g Aggregates, Update, Insert, Delete Named Graph support (i.e. use of logical names to partition RDF data within Virtuoso's multi-model dbms engine)
Inference Engine (currently in use re. DBpedia via Yago and UMBEL)
Host and exposes data from Drupal, Wordpress, MediaWiki, phpBB3 as RDF Linked Data via in-built support for PHP runtime
Available as an EC2 AMI
etc..

OpenLink Data Spaces functionality summary:

Simple mechanism for Linked Data Web enabling yourself by giving you an HTTP based User ID (a de-referencable URI) that is linked to a FOAF based Profile page and OpenID
Binds all your data sources (blogs, wikis, bookmarks, photos, calendar items etc. ) to your URI so can "Find" things by only remembering your URI
Makes your profile page and personal URI the focal point of Linked Data Web presence
Delivers Data Portability (using data access by value or data access by reference) across data silos (e.g. Web 2.0 style social networks)
Allows you make annotations about anything in your own Data Space(s) on the Web without exposure to RDF markup
A Briefcase feature that provides a WebDAV driven RDF Linked Data variant of functionality seen in Mac OS X Spotlight and WinFS with the addition of SPARQL compliance
Automatically generates RDFa in its (X)HTML pages
Blog, Wiki, WebDAV File Server, Shared Bookmarks, Calendar, and other applications that look and feel like Web 2.0 counterparts but emitt RDF Linked Data amongst a plethora of data exchange formats
Available as an EC2 AMI
etc..

OpenLink Ajax Toolkit functionality summary:

Provides binding to SQL, RDF, XML, and Web Services via Ajax Database Connectivity Layer (you only need an ODBC, JDBC, OLE-DB, ADO.NET, XMLA Driver, or Web Service on the backend for dynamic data access from Javascript)
All controls are Ajax Database Connectivity bound (widgets get their data from Ajax Database Connectivity data sources)
Bundled with Virtuoso and ODS installations.
etc.

OpenLink Data Explorer functionality summary

Distills entities associated with information resource style containers (e.g. Web Pages or files) as RDF Linked Data
Exposes the RDF based Linked Data graph associated with information resources (see the Linked Data behind Web pages)
Ubiquity commands for invoking the above
Available as a Hosted Service or Firefox Extension
Bundled with Virtuoso and ODS installations
etc.

Note:

Of course you could have simply looked up OpenLink Software's FOAF based Profile page (*note the Linked Data Explorer tab*), or simply passed the FOAF profile page URL to a Linked Data aware client application such as: OpenLink Data Explorer, Zitgist Data Viewer, Marbles, and Tabulator, and obtained information. Remember, OpenLink Software is an Entity of Type: foaf:Organization, on the burgeoning Linked Data Web :-)

Linked Data Planet Keynote (RDFa based remix edition)
On The Cusp: A Global Review of the Semantic Web Industry.

Comments about recent Semantic Gang Podcast

Fri, 02 May 2008 21:44:31 GMT

After listening to the latest Semantic Web Gang podcast, I found myself agreeing with some of the points made by Alex Iskold, specifically:

-- History is a great tutor, answers to many of today's problems always lie somewhere in plain sight of the past.

Of course, I also believe that Linked Data serves Web Data Integration across the Internet very well too, and the fact that it will be beneficial to businesses in a big way. No individual or organization is an island, I think the Internet and Web have done a good job of demonstrating that thus far :-) We're all data nodes in a Giant Global Graph.

Daniel lewis did shed light on the read-write aspects of the Linked Data Web, which is actually very close to the callout for a Wikipedia for Data. TimBL has been working on this via Tabulator (see Tabulator Editing Screencast), Bengamin Nowack also added similar functionality to ARC, and of course we support the same SPARQL UPDATE into an RDF information resource via the RDF Sink feature of our WebDAV and ODS-Briefcase implementations.

Linked Data Solution for Exposing OpenLink Product Portfolio

Sat, 16 Feb 2008 21:08:17 GMT

At OpenLink Software, we've had an immense problem explaining the depth and breadth of our product porfolio via traditional Document Web pages. Thanks to SPARQL and Linked Data, we are now able to use Web Data Object IDs (HTTP based URIs) to produce super SKUs for every item in our product portfolio. Even better, we are able to handle the additional challenge of exposing features and benefits which by their very nature are mercurial across an array of fronts (products releases, product formats, and supported platforms etc).

Now I can simply state the following using Linked Data (hyperdata) links:

OpenLink Software's product porfolio is comprised of the following product families:

Universal Data Access Drivers Suite (UDA) for ODBC, JDBC, ADO.NET, OLE-DB, and XMLA
OpenLink Data Spaces
Virtuoso

We no longer have to explain (repeatedly) why our drivers exist in Express, Lite, and Multi-Tier Edition formats, or why you ultimately need Multi-Tier Drivers over Single Tier Drivers (Express or Lite Editions) since you ultimately heed high-performance, data encryption, and policy based security across each of the data access driver formats.

Kingsley Idehen's Blog Data Space

Simple Virtuoso Installation & Utilization Guide for SPARQL Users (Update 5)

What is SPARQL?

Why is it important?

How do I use it, generally?

How do I use SPARQL with Virtuoso?

Installation Steps

Troubleshooting

Data Loading Steps

SPARQL Endpoint Discovery

Related

Solving Real Problems by Leveraging Linked Data: Unambiguous & Verifiable Identity for HTTP Networks

Problem: Unambiguous Verifiable Network Identity.

WebID Components

Demo

Related

Revisiting HTTP based Linked Data (Update 1 - Demo Video Links Added)

What is Linked Data?

Why is it Important?

How is Linked Data Delivered?

How are Linked Data Object Representations Structured?

How Do I Create Linked Data oriented Hypermedia Resources?

Practical Examples of Linked Data Objects Enable

How Do OpenLink Software Products Enable Linked Data Exploitation?

Related

Linked Data & Socially Enhanced Collaboration (Enterprise or Individual) -- Update 1

How HTTP based Linked Data Addresses the Identifier Issue

How FOAF+SSL adds Socially aware Security

Conclusions

Related:

5 Game Changing Things about the OpenLink Virtuoso + AWS Cloud Combo

Introducing Virtuoso Universal Server (Cloud Edition) for Amazon EC2

What is it?

What does it offer?

How Do I Get Going with It?

Where Are All the RDF-based Semantic Web Applications?

Virtuoso Universal Server functionality summary:

OpenLink Data Spaces functionality summary:

OpenLink Ajax Toolkit functionality summary:

OpenLink Data Explorer functionality summary

Note:

Related

Comments about recent Semantic Gang Podcast

Linked Data Solution for Exposing OpenLink Product Portfolio