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A Type

This term is in the "new" area - implementation feedback and adoption from applications and websites can help improve our definitions.
The ConstraintNode type is provided to support usecases in which a node in a structured data graph is described with properties which appear to describe a single entity, but are being used in a situation where they serve a more abstract purpose. A ConstraintNode can be described using constraintProperty and numConstraints. These constraint properties can serve a variety of purposes, and their values may sometimes be understood to indicate sets of possible values rather than single, exact and specific values.
PropertyExpected TypeDescription
Properties from ConstraintNode
constraintProperty Property  or
Indicates a property used as a constraint. For example, in the definition of a StatisticalVariable. The value is a property, either from within or from other compatible (e.g. RDF) systems such as or
numConstraints Integer Indicates the number of constraints property values defined for a particular ConstraintNode such as StatisticalVariable. This helps applications understand if they have access to a sufficiently complete description of a StatisticalVariable or other construct that is defined using properties on template-style nodes.
Properties from Thing
additionalType Text  or
An additional type for the item, typically used for adding more specific types from external vocabularies in microdata syntax. This is a relationship between something and a class that the thing is in. Typically the value is a URI-identified RDF class, and in this case corresponds to the use of rdf:type in RDF. Text values can be used sparingly, for cases where useful information can be added without their being an appropriate schema to reference. In the case of text values, the class label should follow the style guide.
alternateName Text An alias for the item.
description Text  or
A description of the item.
disambiguatingDescription Text A sub property of description. A short description of the item used to disambiguate from other, similar items. Information from other properties (in particular, name) may be necessary for the description to be useful for disambiguation.
identifier PropertyValue  or
Text  or
The identifier property represents any kind of identifier for any kind of Thing, such as ISBNs, GTIN codes, UUIDs etc. provides dedicated properties for representing many of these, either as textual strings or as URL (URI) links. See background notes for more details.
image ImageObject  or
An image of the item. This can be a URL or a fully described ImageObject.
mainEntityOfPage CreativeWork  or
Indicates a page (or other CreativeWork) for which this thing is the main entity being described. See background notes for details.
Inverse property: mainEntity
name Text The name of the item.
potentialAction Action Indicates a potential Action, which describes an idealized action in which this thing would play an 'object' role.
sameAs URL URL of a reference Web page that unambiguously indicates the item's identity. E.g. the URL of the item's Wikipedia page, Wikidata entry, or official website.
subjectOf CreativeWork  or
A CreativeWork or Event about this Thing.
Inverse property: about
url URL URL of the item.

More specific Types