Databases and collections are accessible in WorldCat Discovery via a central index of metadata from multiple content providers or via remote access from a subscription provider’s site. The content provider determines whether their database is represented in the central index or as a remote database.
WorldCat and WorldCat.org
WorldCat is a database that represents the “collective collection” of the world’s libraries, built through the contributions of librarians, and expanded and enhanced through individual, regional, and national programs. WorldCat represents electronic and digital materials, including the important, unique items found only in local libraries.
WorldCat.org is a web destination that brings together the contents of the WorldCat database, including the multiple formats contributed through the WorldCat Digital Collection Gateway and more than 200 million article citations from many popular databases.
The central index is a rapidly growing collection of metadata for licensed resources built from databases provided to OCLC by various content providers. When searching these databases, WorldCat Discovery queries its central index and returns records matching the search terms.
About the Central Index:
- Central index databases contain article citations from non-OCLC databases.
- Bibliographic records display key metadata such as title, author, and publication information
- Articles from non-OCLC central index databases display the database name as the source of the citation
- Your library must subscribe to a central index database to enable it
- Database contents in OCLC’s central index are generic and not specific to your library
- OCLC has no way of knowing from the central index databases what content falls within your actual subscription coverage
- Articles display as held by your library based on the assumption that, because your library has holdings on the serial where the article is found, you have access to the articles within that serial
- Content providers are required to give OCLC certain metadata, but they are not required to provide all their metadata for centrally-indexed databases. This may cause differences in the results returned in WorldCat Discovery compared to searching the provider platform directly.
- Central index records cannot be merged, which may result in multiple records for the same article from different sources. A clustering algorithm is used to group related records and it is tweaked periodically. New data is continuously being added, and fixes to the algorithms can cause small changes in clustering each time the process is run.
The metadata for remote databases is contained on the database provider’s platform. When searching a remote database from WorldCat Discovery, the search is performed via a federated connection to the providers’ platform and results are then returned to WorldCat Discovery.
Providers may not always support the same indexes in the federated version of their platform as they do in the native platform, which may lead to discrepancies between the search results returned in WorldCat Discovery and results from searching the provider platform directly.
- ProQuest subscribers:
For mutual subscribers to WorldCat Discovery and ProQuest remote databases, when a user chooses a ProQuest database recommendation from the additional databases searched section, they will link from the WorldCat Discovery interface directly into the database chosen with the search re-executed on the ProQuest platform. They will then be able to explore the results of the search on the ProQuest platform without having to execute the search again.
How to search available content
Consult the available collections and databases to see whether a database is included in the WorldCat Discovery central index or is searched remotely.
When a search is conducted against both centrally-indexed and remote databases, the search query is submitted to the OCLC central index and the content provider platform.
Matching records from the central index databases and from each of the remote databases are combined into a single set of matching records. The chosen relevance algorithm is then applied to the combined set of records to rank them in the WorldCat Discovery results display.
For more information and configuration options, see:
Remote database preview
After a search is entered, if your institution has configured remote databases for your institution, WorldCat Discovery displays those database recommendations in the remote database preview drawer on the search results screen. The remote database preview drawer allows users to review their search results while alerting them to the additional resources in remote databases.
Each remote database result displays the name of the database and an approximate number of search results. To view remote database results, click on the database box. The database will display the search results in its native interface in the browser.
The heading of the remote database preview drawer depends on the database responses and is chosen using the following order of precedence:
At least 1 database that has:
Preview drawer heading
Relevant matches exist in additional databases
Failed to return results
Visit these additional databases to view content that might match your search terms
No matches exist in additional databases
Click the See all button to expand the drawer to display databases grouped under the above headings.
Central index results appear below the remote database suggestions.
- ProQuest subscribers:
If your institution provides access to remote databases:
- OCLC recommends including a maximum of ten remote databases in your default setting.
- Review your institution's remote database access credentials in OCLC Service Configuration > Metasearch Content > Default Databases and Licensed Content to ensure they are up to date.
- If your database access credentials and proxy URL settings are accurate, no additional changes are necessary. Existing remote database configurations for remote searching will remain active.
- A prompt will appear when the staff user attempts to view records in WorldCat Discovery that require authentication. You can customize the text that appears in the prompt. See User Interface Options, Authentication Prompt for Restricted Content for more information.