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Overview of Taxonomies

A taxonomy is a vocabulary collection based on SKOS, the W3C standard ontology designed for representing taxonomies, thesauruses, and subject heading schemes.

In EDG, Taxonomies are SKOS-based datasets, whereas other datasets typically do not include SKOS, although they may. When a new taxonomy is created, EDG will automatically include SKOS ontology. SKOS provides description of concepts and their properties e.g., fields like preferred and alternative labels, various notes and relationships.

Edit application for taxonomies is designed to offer SKOS-based features, such as displaying a SKOS model's Concept Hierarchy (where concepts are connected by SKOS "broader" statements) starting with the defined Concept Schemes as hierarchical roots. Every taxonomy must have at least one concept scheme that identifies "top concepts" in a scheme.  A taxonomy can have multiple concept schemes; however, a better practice can be to use a single concept scheme per individual taxonomy. Since taxonomies can, as all asset collections, be included into each other, a taxonomy with multiple concept schemes can be assembled through inclusion of several single concept scheme taxonomies.

Use of the pre-defined SKOS fields can be configured locally for a given taxonomy, globally for the entire EDG or for a subset of taxonomies e.g., all taxonomies associated with some business area. You can disable fields for all or a group of taxonomies by taking advantage of the Ontology modeling functionality in EDG. Ontologies are also used to define custom, non-SKOS properties for taxonomy concepts and to define specializations (sub classes of concepts). If you customize SKOS, you need to make sure that the ontology with your customizations is included in the taxonomies these customizations apply to. There is a system-wide setting your EDG administrator can use to ensure that the customized model is included in every new taxonomy. If customization only applies to a subset of taxonomies, creator of a taxonomy can use the Includes dialog to include the desired customized model.

Features supported only for Taxonomies but not available for other asset collections are identified in this guide with the following:


This feature is available only for taxonomies.

Taxonomies Home

Selecting the Taxonomies link in the left-navigation pane of TopBraid EDG lists all of the Taxonomy collections currently available to the user and, it allows authorized users to create new ones.

Prerequisites: Licensing and Enablement

The availability of any collection type (including Taxonomies and customer-defined types) is determined by what is (a) licensed and (b) configured under Server Administration. To install a license or to view the currently licensed features, see Setup > Product Registration. To configure which licensed collection types are currently enabled or disabled, see EDG Configuration Parameters > Configure Asset Collection Types. For general licensing information, see the TopQuadrant website, which describes the TopBraid products and the  data governance packages that determine the available collection types.


Listing of Taxonomies

This home view shows a table with all Taxonomies that you can access in some way. For each collection some brief metadata is available in columns of the table. Columns are sortable and you can filter content of the table by typing search strings in the Refine field at the upper right of the table. To access an asset collection, click on its link.

To create an asset collection click on Create New Taxonomy button. 

You can also select an asset collection in the table and start a workflow for it.

This page provides a focused view on Taxonomies. To see a view of all asset collections, irrespective of their type, that you have a governance role for, click on your User Name in the upper right corner of the page. To see all asset collections you have access to organized by their subject areas, click on the Governance Areas link in the left hand-side vertical Navigation Bar.

If a Taxonomy is either missing or it is lacking expected features in your views, you or your security role(s) may lack proper permissions for the Taxonomy.  A manager of the Taxonomy can give you the needed permissions via its utilities' Users settings. For background information, see Asset Collection Permissions: Viewer, Editor, and Manager.

Another possible cause of a missing feature is that it requires administrative setup to become active. See EDG Administration for relevant within-application settings and/or see other EDG Administrator Guide documents for relevant external installation and integration setup.

Create New Taxonomy

The Taxonomies > Create New Taxonomy link opens a form with fields used to define the new Taxonomy. Note that you can also create a Taxonomy by using a Create link in the Governance Areas page. 

Nobody will have a link for creating any asset collection until an administrator configures EDG's persistence technology as documented in Server Administration: Teamwork Platform Parameters: Application data storage . Additionally, each user will not have a create link unless the user or their role has a Create permission for the EDG Repositories project as documented in  EDG Rights Management .

The Create dialog creates a new Taxonomy and automatically grants the Creator a Manager's permission for it. When Taxonomy creation starts from the Governance Areas page, new Taxonomy is automatically associated with the selected area. When Taxonomy creation starts from the Taxonomies home page, new Taxonomy is not connected to any governance area. To change this after creation, update in utilities: Settings > Metadata > Edit > subject area

The Create dialog box asks for the Taxonomy's Label (name), its Default namespace and, optionally, a Description. The default namespace will be used to construct URIs (unique identifiers) for the resources in the Taxonomy. EDG will automatically pre-populate the default namespace based on the system-wide, configurable settings. Creator can change it. Recommended practice for all collection types is to use a '/' (slash) at the end of the default namespace. For ontologies, it is typical to use '#' (pound sign). However, '/' can be used as well. 

Search Indexing

If using Search the EDG with Lucene indexing (the default option), the Create dialog will offer an option to add this collection to the index. You can later change this setting at the Manage tab.

URI Construction Rules

The Create dialog will also offer you an option to specify URI generation patterns for instances for each newly created graph. There are 3 different options to choose from:



  • New Instances Class Prefix has a selection of: Default, name and acronym. Default means that after a namespace the local name will be added. In case of name and pattern the name or pattern will be added in between the namespace and local name.

    Acronym property is set for most of the asset collections in EDG, however, if you can't find acronym property in your model an extra setup needs to be done. By default ontologies don't have the edg:acronym property defined in a model. It requuries creating a a property SHAPE on an edg:acronym (<http://edg.topbraid.solutions/model/acronym> property. The shape would need to associate the property with all instances of RDFS class (in a Manage tab change Root Class of Hierarchy to rdfs:Class, add edg:acronym property to rdfs:Class with the appropriate SHAPE defined, then change the root class to owl:Thing and start adding acronym to a class for which instances will be using acronym in their URI pattern)
  • New Instances Construct Method allows to choose from: Default, label, uuid, counter, or custom. In this case, the local name would be either predefined by the label, uuid or counter. The Default option will be a label. Custom option allows creation of a completely custom URI (namespace and local name).

    To use custom instances construct method you'd need to provide a custom method of URI creation.  It requires creating a new SWP file in IDE, importing swa.ui.ttlx, and overwriting ‘swa:createResourceDialogUsingCustom’ class accordingly.

  • New Instances User Cannot Modify URI: Default, true or false provides the option to allow modification to the URI during the creation of assets in the asset collection. By default, Create dialog for assets will allow users to modify URI

This setup can later be changed. The option is available in the Manage tab. This however wouldn't change the already created instance URIs, but will take effect for the new ones.

Includes

Collections often have natural relationships to other collections (e.g., each reference dataset's main entity class is defined in an included ontology). Any collection using outside resources needs to include the collections that contain them. Some inclusions might be required while others might merely be permitted. For example:

  • Taxonomies always include the SKOS ontology, and they may include other taxonomies.
  • As mentioned above, each reference dataset and data graph must include at least one ontology to define the dataset's entities.
  • Glossaries always include the pre-defined EDG ontology that describes business glossary terms.
  • Catalogs of data assets always include the pre-defined EDG ontology describing data assets and are expected to include definitions of relevant physical datatypes.

These requirements can be further configured. When creating a collection, any required reference to another collection will either be handled automatically or be presented for selection. 




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