FAST Changes
Log of updates to FAST Subject Headings
Recent FAST changes
FAST Update Strategy and Logistics
The FAST Authority file is updated periodically and is made available by OCLC under the Open Data Commons Attribution License (ODC-By): http://www.oclc.org/research/activities/fast/odcby.htm. Periodically, the entire set of FAST files is made available for download at FAST Dataset Download These are updated about every 6 months.
To maintain and enhance FAST, updates to the FAST Authority file are more frequent. These more current updates to individual records are available though the searchFAST interface or through Linked Data on a per record basis if needed. The changes are summarized on this page.
Reasons for Updates:
Since FAST is derived from the Library of Congress (LC)Subject Headings and Names files, we update FAST periodically to follow changes to those files. Most Library of Congress changes are incorporated monthly, although some require further review and take a little longer. Also, FAST incorporates substantial linking information to other authority files, such as VIAF and Geonames, and these links are reviewed and updated periodically. Of course, routine maintenance, enhancements, and corrections also are reasons for updates.
Update Change file format
To create an easy reference for changes to the FAST authority file, the changes are recorded in a spreadsheet.
Change Type | FAST Number | Current Heading | Former Heading | Linking Entry | Additonal Linking Entry | Notes (this column is not in spreadsheet |
---|---|---|---|---|---|---|
New Heading | fst###### | New Heading | [blank] | LCSH/NACO heading | LCSH/NACO heading (as needed) | |
Modified Heading | fst###### | Modified Heading | Former Heading | LCSH/NACO heading | LCSH/NACO heading (as needed) | |
Other Changes | fst###### | Current Heading | [blank] | LCSH/NACO heading | LCSH/NACO heading (as needed) | The main heading is unchanged for this record. 4xx, 5xx or 7xx or other fields may have changed. |
Deprecated | fst###### | [blank] | Former Heading | FAST replacement heading | 7XX links are for the replacement FAST headings. Links to LCSH/NACO are less interesting now. | |
Split | fst###### | [blank] | Former Heading | FAST replacement heading | FAST replacement heading (as needed) | 7XX links are for the replacement FAST headings. Links to LCSH/NACO are less interesting now. |
Obsolete | fst###### | [blank] | Former Heading | LCSH/NACO heading | LCSH/NACO heading (as needed) | The referenced LCSH/NACO headings may provide information about why these headings were made obsolete or deleted with no replacement headings specified. |
Date and Time of Last Transaction
In MARC, the 005 field records the date and time of the last transaction for a record. We always follow this practice for any substantial change to the record, such as the authorized or see also headings. However, since FAST incorporates more 'living' information, such as the annual count of how frequently the heading is found in WorldCat, resetting the time stamp would mask the date of the last substantive change. Examples of changes that don't result in Transaction date changes are: validation and replacement of VIAF or other links, updates to usage statistics, and minor clerical updates that touch a large number of records. A MARC Change File will be made available for any change that results in a Date and Time of Last Transaction change.
FAST Record Numbering
FAST strives to associate a FAST number with a concept. If the string representing the concept changes, the FAST number will be kept the same. This follows LC practice, and generally a LC control number (LCCN) will always be associated with the same FAST number
When two concepts are merged, the now non-preferred heading is deprecated in favor of an existing concept. Deprecated records contain links to the replacement records, and the new records have a reference to the old form of the heading. These are clearly indentified in the MARC version for the records, and appropriate mappings are made of this information to the RDF versions.
If a concept is split into two or more concepts, new numbers are assigned to the new concepts and the original FAST number will be deprecated. For example, "Nurses and Nursing" was split into two concepts, "Nurses" and "Nursing", and two new numbers are assigned.
At first FAST attempted to control both the FAST number and heading string as a pair. If an authorized heading string changed, a new FAST number was assigned, and the heading string was not reused. This became impractical, so the practice was discontinued. Many deprecated records are still in FAST that record the complete earlier form of the record.