FAQs - v2

Why are records found in WorldCat.org not available in the WorldCat Search API?

The WorldCat Search API includes all the records found in the cataloged WorldCat database.  These are the records found within the Connexion WorldCat database or in the FirstSearch WorldCat database.  It is all the records contributed to OCLC through our cataloging libraries. 

The WorldCat.org database includes all of these cataloged WorldCat records and also many other records, primarily articles, that have been added to this database from other sources.  Those records not in the cataloged WorldCat database display in WorldCat.org with information about their source in the label “Database”.  While they have OCLC record numbers that will retrieve these records in WorldCat.org, they are not part of the WorldCat Search API database. 

Why are keyword search result counts different, in the API, FirstSearch and WorldCat.org?

There are a couple of reasons for this. WorldCat.org includes article citation and digital materials descriptions that are not searched in the API or FirstSearch interfaces to the WorldCat database, so its results tend to be larger. The API and FirstSearch results should match, but the API result counts may be lower if a client chooses to group items, rather than view a flat list of individual bibliographic records.

What are the limits currently encountered in the service?

• Query size
  There is a limit on the number of terms that can appear in the query passed to the API. No more than 50 terms can be passed in a single query to the API.
• Number of queries per day
  There is a limit to the number of queries available within a single day set for each wskey. Initially all Member's keys have a limit of 50,000 queries a day set as a rolling 24 hour limit. Libraries can request this be raised. If you would like to have your limit increased please send a request to OCLC support staff  via our contact form.
• Maximum number of library holdings –
  For any query the maximum number of holdings that can be paged through is 500. 
• Total maximum number of bibliographic records for a single specific query –
  For any specific query, it is possible to page through all the results up to the 10,000th record. After that point, the system will appear to continue to page, but the next result will be a repeat of an earlier record.

Is it possible for an institution to have more than one wskey?

Yes, it is possible and even ideal for a variety of reasons. There may be more than one IT group involved in different projects. Or it may be that you’d launch different applications with different keys. If you already have a key and would like another one, please send a request to the OCLC support staff via our contact form.

What does setting groupRelatedEditions and groupVariantRecords to true do?

In WorldCat there tends to be a different bibliographic record for each new publisher or edition or type of format for a title. Because too many library users there can appear to be very little difference between these, groupRelatedEditions is offered to reduce the appearance of duplicates.  Setting groupRelatedEditions to true pulls together bibliographic records with the same authors/creators and titles. Then the group of records is represented by the most widely held bibliographic record for that grouping.  It also provides all the library holdings information for the group of records as one set of holdings.

Another method to reduce duplicates is by grouping variant records. WorldCat contains metadata descriptions for the same item in many different language. Setting groupVariantRecords to is offered to bring together these metadata descriptions of the same edition of an item in different languages. Then the group of records is represented by the preferred language specified by the client. It also provides all the library holdings information for the group of records as a set of holdings.

Setting groupRelatedEditions and groupVariantRecords to false will return each bibliographic record, without trying to remove any perceived duplication between edition or metadata descriptions. Setting groupRelatedEditions and groupVariantRecords to false for library holdings information, only returns holdings when a library has set it on that SPECIFIC bibliographic record.