16.6. Automated Generation of Linked Data Views over Relational Data Sources
16.6.1. Introduction
Virtuoso offers from Conductor UI an HTML based Wizard interface for dynamically generating & publishing RDF based Linked Data from ODBC or JDBC accessible relational data sources. Basically, a mechanism for building RDF based Linked Data views over relational data sources.
The proliferation of relational databases across enterprises and behind Web sites, makes them a vital data source for the burgeoning Linked Data Web. Thus, the process of publishing Linked Data from these sources needs to be as unobtrusive as possible. Naturally, a balance has to be struck between unobtrusive generation of Linked Data and traditional relational database management system (RDBMS) virtues such as:
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Scalability
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Security
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Analytical Expressivity of SQL
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Separation of Data Access and Data Storage via ODBC, JDBC, ADO.NET CLIs.
The following steps must be taken to publish RDF-based Linked Data:
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Identifying ODBC or JDBC data sources that host the data you seek to publish (assuming the data isn't Virtuoso RDBMS hosted -- in which case, skip ahead to step #3).
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Attach/Link TABLEs or VIEWs from the external data sources into Virtuoso via their Data Source Names (DSNs).
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Identify the internal or external TABLEs or VIEWs that hold the data you wish to publish.
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Configure Endpoints and Re-write Rules to disambiguate data object (resource) identity and description through HTTP-based content negotiation.
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Expose the Data Source Ontology and associated Instance Data in Linked Data form through those Endpoints and Re-write Rules.
These steps may be largely automated (the "One-Click" Deployment below), or performed manually ("Using the Conductor's HTML-based Wizard" further down).