What is PCI?
The Primo Central Index (PCI) is an aggregated index of hundreds of thousands of scholarly journals articles, in addition to many other resource types. You search this index when you search the "Everything" scope in Primo. The index includes articles from publishers, aggregators, and open access data sources.
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In PCI, there was a single facet for Audio-Visual. In CDI, these will now be separate facets (Audio, Visual). Full comparison of resource types.
Search and ranking
Ex Libris documentation on search and ranking.
Record source facet
The Record source facet is restricted to collections that are full text available. Content that is searchable only (and not full text available) is excluded from the facet.
Are there any known issues?
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For several restricted ProQuest A&I collections, records are deliberately excluding from merging (e.g. the miscellaneous collections such as Sociological Abstracts, International Bibliography of the Social Sciences, Humanities Index). ProQuest offers the same title in different packages with different landing URLs which can create linking problems when the records are merged. There is an initiative underway to support package level linking, which will allow the records to be merged in the future.
Known gaps and issues
Harvard is keeping a local list of CDI Known Issues under investigation. Ex Libris maintains a full list of gaps and issues, and when they will be resolved.