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    The Ex Libris Central Discovery Index (CDI) – An Overview


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    The Ex Libris Central Discovery Index (CDI) is a central, unified index, for scholarly and academic material worldwide. It contains over 5 billion records and many different resource types from thousands of publishers, aggregators, and repositories.

    CDI is content neutral and indexes any type of subscribed, purchased or open access content that is of use for research, teaching, and learning. While CDI primarily focusses on metadata, it also indexes full text for part of the content. In addition to what is indexed, CDI encompasses a suite of services available via an API and our discovery systems, Primo and Summon.

    CDI leverages a new infrastructure to provide the scale required to meet today’s needs and future requirements. This enables fast content updates and new content ingestion cycles on a large scale, continuous content enrichment, and reliable performance resulting in fast response times and other operational efficiencies.

    While the ability to scale is important, operational processes focus as much on data quality. Our data excellence program focusses on the continuous improvement of processes and tools to provide high quality data. CDI is supported by the Ex Libris content services team.

    In academic publishing many platforms offer the same content and provide metadata for the same records. In CDI we deduplicate these records and create one unified merged metadata record. For content from which we do not ingest metadata directly from a provider, CDI automatically provides alternative coverage from other metadata sources.

    Primo VE Essentials: Central Discovery Index (5 min)

    CDI Services - Quicklinks, bX, and More

    Libraries subscribe to and access the full text of their content on many different platforms. Among other linking options, CDI provides the Quicklinks service to supply direct links to the PDF and HTML full text. Quicklinks can be embedded directly into the records on the discovery user interfaces and are also available via API.

    Other CDI services include the bX recommender, a citation trail that allows users to browse between items that cite each other in an exploratory trail, and a relationship graph (related items service) that connects items such as books, book chapters, and book reviews visually on the user interface for users to access.

    Managing Your Subscriptions and Free Content in CDI

    CDI provides a single activation process for libraries using Primo and Summon with Alma, SFX (for Primo), and the 360 Client Center (for Summon) to publish subscribed and free content to their users and to make it discoverable.

    To support the different needs of our global customer base, Alma customers can choose between the FullyFlexible and EasyActive settings. The FullyFlexible setting enables libraries to control what is searchable beyond their library collection (what they have available in full text, either because it is subscribed or because it is open access), they therefore manage their search activations themselves. Through the EasyActive setting all content (with a few documented exceptions) is automatically searchable with only what the library activates being flagged as available in full text.

    Activations in Alma, SFX, or 360 are published to CDI and processed to become available for users within 30 to 40 hours. A new process in development will reduce the processing time to an average of 24 hours.


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