Area 2 provides definitions for the glossary. This enables the definition of meanings and the relationships between different types of terminology. Most definitions are created through a manual process, however, this definition may occur in a different tool and be replicated automatically into other metadata repositories. There can be multiple glossaries in the metadata repositories. Each glossary owns a set of Glossary terms and (optionally) a category hierarchy. Glossary terms can be linked into none, one or many categories, from any glossary.
Figure 1 shows the packages for the glossary.
Figure 1: Packages for area 2 - the glossary |
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Each package will be defined in its own model file <package-name>.json and added to the addons/model directory in the atlas build tree.
Glossary Object
An Apache Atlas repository may contain many glossaries, particularly when it is part of a bigger enterprise cluster of repositories. Each glossary may come from a specific team or external organization. Or it may be focused on a particular topic or set of use cases. Figure 2 shows how a glossary is defined.
Figure 2: The glossary providing the anchor point for the glossary content | The anchor for each glossary is the Glossary object. The classifications used with the glossary object are used to document the type of vocabulary it contains and its purpose: |
Category Hierarchies
The vocabulary for the glossary is organized into a hierarchy of categories. The categories are effectively a folder structure for the glossary. Some of these categories represent the terms for a subject area and this is identified using the SubjectArea classification. The categories may follow a formally published category hierarchy. The LibraryCategoryReference classification is used to document the links to the external category's reference Id.
Figure 3: The category hierarchy |
Terms
The vocabulary for the glossary is documented using terms. Each term represents a concept of short phrase in the vocabulary. A term is owned by a glossary but can be linked into a category from any glossary. Figure 4 shoes the glossary term.
Figure 4: Terms |
Dictionary
The dictionary model adds some basic term relationship used to show how the meanings of different terms are related to one another. Figure 5 shows the dictionary model.
Figure 5: The dictionary model |
Spine Objects
The spine object model adds the relationships that enable a glossary to contain the definition of spine objects that can be used to control access to data, and the guild the design of new data stores and APIs. Figure 6 shows the relationships and classifications used to describe spine object.
Figure 6: Spine Object Model |