This guide forms the introduction to the set of GraphDB user documentation. GraphDB is Ontotext's database system for storing, processing and querying structured data formatted according to the Resource Description Framework (RDF). It is packaged as a Storage and Inference Layer (SAIL) for the Sesame RDF framework. If you need a quick overview of GraphDB or a download link to its latest releases, please visit GraphDB product page.
Among structured data repositories, GraphDB is the world leader for its unsurpassed processing capacity, both in terms of volume of data and loading/inference speed on commodity hardware.
This guide provides the reader with a conceptual overview of GraphDB – with some general information about its structure and functioning – as well as an overview of how to install the system.
In addition, a large part of the document gives a general introduction to semantic concepts and technologies, which provides the inexperienced reader with sufficient background to understand the role of OWLIM and the problems it solves.
This document is intended for project managers, engineers and systems designers who wish to integrate GraphDB in to their applications, but who do not necessarily have a thorough grounding in semantic technologies and concepts. It is also useful for system administrators who need to support and maintain an GraphDB-based system.
This document presumes that the reader is familiar with databases and is expected to be able to draw from his knowledge of relational databases. The required minimum of Semantic Web concepts and related information is provided in the course of this document.
An understanding of XML would also be beneficial, as it is the most widely used meta-data description language on the Web and for this reason is used as a standard method for illustrating Semantic Web concepts in the reference literature.
The purpose of this document is:
- To deliver a general overview of the GraphDB system and to acquaint the reader with its architecture and operational logic
- To introduce the Semantic Web and its concepts and to provide enough information to begin using GraphDB in practical applications
The [background knowledge] section gives a brief conceptual description of the Semantic Web. There is a great deal of information about the Semantic Web available both over the Internet and in print, therefore the topics in this section serve to highlight the required knowledge rather than to cover them in great depth. However, ample references are provided for every topic.
The [introduction to GraphDB] section deals with GraphDB itself and provides introductory information that forms a basis for the more detailed information given in the User Guide for the particular GraphDB edition.
The [background knowledge] section is optional depending on the reader's familiarity with Semantic Web concepts. For readers unfamiliar with this subject, it is recommended to read this entire section first and preferably check as many of the references as time permits. Readers who have some understanding, should read this section selectively, skipping over content that is already familiar. Experts in this field can skip the entire section.
The [introduction to GraphDB] is essential reading and should be read sequentially from beginning to end without skipping any topics. This knowledge is required before using GraphDB.
The following formatting conventions are used in this book:
- Code examples are listed in typewriter-like font.
- The first occurrence of a term that is explained in the Glossary at the end of this book is hyper-linked to its Glossary entry and is formatted .
- Other important terms, when first introduced, may be written in italics.
- Formulas are always in italics.
- References are given in square brackets, e.g.  means "Refer to item #3 in the References section".
GraphDB uses Sesame as a library, taking advantage of its APIs for storage and querying, as well as the support for a wide variety of query languages (e.g. SPARQL and SeRQL) and RDF syntaxes (e.g. RDF/XML, N3, Turtle).
The development of GraphDB is partly supported by SEKT, TAO, TripCom, LarKC, and other FP6 and FP7 European research projects.
This document and the products discussed in it are copyrighted and subject to licensing as follows:
- GraphDB-Lite, © Copyright Ontotext AD. 135 Tsarigradsko Shosse, Sofia 1784, Bulgaria, http://www.ontotext.com.
- GraphDB-SE, © Copyright Ontotext AD. 135 Tsarigradsko Shosse, Sofia 1784, Bulgaria, http://www.ontotext.com.
- GraphDB-Enterprise, © Copyright Ontotext AD. 135 Tsarigradsko Shosse, Sofia 1784, Bulgaria, http://www.ontotext.com.
- Sesame, © Copyright Aduna b.v. Stadsring 181, 3817 BA Amersfoort, The Netherlands Sesame is an open-source library, available under the GNU Lesser GPL (http://www.gnu.org/copyleft/lesser.html)
- All other trademarks mentioned in this document, belong to their respective owners.
Full licensing information is available at http://www.ontotext.com/owlim/, as well as in the licence files located in the main folder of the distribution package.