Vocabularies: Local, AAT, LCSH and more
CollectiveAccess supports both standard and local controlled vocabularies. The standard authorities most frequently used in CollectiveAccess are The Getty Art and Architecture Thesaurus (AAT) and Library of Congress Subject Headings (LCSH). Although both vocabularies are external resources, CollectiveAccess handles them differently, primarily because the AAT requires a fee-based license, whereas the LCSHs are free to use.
- Update as of 2015: The Getty vocabularies are now available as Linked Open Data. See here for more information. The below is still applicable for users who would like to import the entirety of the vocabularies into their local system via the paid XML-based license package.
The AAT can be imported into your system using the XML UTF-8 format available after purchase. An import script named import_aat.php is located in support/data/aat/. The import utility supports the ingestion of preferred terms, parent-child relationships between preferred terms, alternate ("non-preferred" in AAT terminology) terms, associative relationships between terms and descriptive notes for preferred terms.
Unlike the AAT and other CollectiveAccess vocabularies that are treated as Lists (and controlled through the Lists and Vocabulary Manager), Library of Congress Subject Headings are handled through a lookup and are therefore accessed through a metadata element. The steps for creating a LCSH lookup field in an installation profile are almost exactly the same as creating an element of any other type: the element set must be declared (in this case with 'LCSH'), the settings must be established and the type restrictions must be configured. The LCSH field supports a ‘vocabulary’ setting that allows users to restrict which particular vocabulary they want to draw from, for example ONLY the Names Authority File. If left unset, the field queries all vocabularies.
Many users chose to create a local vocabulary which they create and include in the installation profile or build on over time. Doing so is easy because vocabularies are treated just like any other list (explained above in section 22.214.171.124), the only difference is that the vocabulary token in the list header definition is set to “1” for true:
<list code="subjects" hierarchical="0" system="0" vocabulary="0">