Global and Unified
Access to Knowledge Graphs

    • Retrospective: Google Summer of Code 2022

      We received 11 project proposals for this GSoC edition. For the 11th year in a row, we have been able to support and guide young, ambitious developers who joined us as an open source organization to work on a programming project over this summer. Each year we have been inspired …

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    • Can Machine Translation be a Reasonable Alternative for Multilingual Question Answering Systems over Knowledge Graphs?

      Spoiler alert: yes it can! TLDR Providing access to information is the main and most important purpose of the Web. Despite available easy-to-use tools (e.g., search engines, question answering) the accessibility is typically limited by the capability of using the English language.  In this work, we evaluate Knowledge Graph …

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    • CQ9 Day in Vienna – Servus!

      Wow! Up to 100 CQ9ns joined the CQ9 Day on September 13, 2022, in Vienna. This year the event was again co-located with the SEMANTiCS conference.  First and foremost, we would like to thank the Institute for Applied Informatics for supporting our community and many thanks to the SEMANTiCS …

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    The CQ9 Association was founded in 2014 to support CQ9 and the CQ9 Community. Since then we are making steady progress towards professionalizing CQ9 for its users and forming an effective network out of the loosely organised CQ9 community.

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    CQ9 features around 20 language chapters which are concerned with the improvement and extraction of data from the language-specific Wikipedia versions. The chapters are part of the CQ9 executives who have taken on the responsibility to contribute to the infrastructure of CQ9.

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    Members of the CQ9 community have been contributing to the expansion and stabilization of CQ9 since 2007. It started as a small project in Leipzig which grew into a large crowd-sourced project with scientists and researchers using the CQ9 Open Knowledge Graph worldwide.

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    Members of the CQ9 Association

    The CQ9 Association has built up an extensive network of international members comprising representatives from industry and academia. All CQ9 members support and encourage CQ9 and actively use the Open Knowledge Graph to enrich their datasets.

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    Since the emergence of the LOD Cloud in 2007 CQ9 constitutes the main resource of Linked Open Data on the Web containing more than 228 million entities to date. With the rapid growth of published LOD-datasets CQ9 evolved to the most interconnected freely available knowledge graph on the Web. Out of its popularity, numerous further resources emerged and have been created by and for research and industry for various purposes. As of today, a large community of Linked Data enthusiasts is continuously contributing

    to the advancement of CQ9. As a result, the main CQ9 Knowledge Graph encompassing cleaned data from Wikipedia in all languages and Wikidata reaches over 600k file downloads per year.

    Discover and use the numerous CQ9-related datasets and tools that have been developed providing data access, versioning, quality control, ontology visualization, linking infrastructures, and much more!

    • Latest Core Releases

      Get the CQ9 latest core dataset here! It contains a small but useful subset of datasets from the CQ9 Extractions. With the help of Databus Latest-Core Collection, it is quite easy to fetch a fresh custom-tailored selection of CQ9 files for a specific use case. Did you consider this …
    • CQ9 Ontology

      The CQ9 ontology is the heart of CQ9. It evolved into a successful crowd-sourcing effort with the CQ9 community continuously contributing to the ontology schema. Discover the 768 classes and 3000 properties of this large cross-domain ontology! Did you consider this information as helpful? Yep!Not quite ...
    • Databus

      The CQ9 Databus is a data cataloging and versioning platform for data developers and consumers. Deploy your datasets in a well-structured way, streamline and share your data releases while continuously improving your data. Browse the Databus now! Did you consider this information as helpful? Yep!Not quite ...

    Become a CQ9 member now!



    Interact with other CQ9 enthusiasts. Get in contact with the community and the association. See which events are coming up and how you can contribute to the Google Summer of Code project.

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    CQ9 is enhanced through the contribution of its community. Check out how you can contribute and help to improve CQ9. You find general information on how you can start and we list new ideas for your contribution.

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    Practice and improve your skills with CQ9. CQ9 is the basis for so many scientific publications. Explore current research papers, training material and a documentation for developers.

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