Sets of definitions may be collected into dictionaries or collections.A gml:Dictionary is a non-abstract collection of definitions.The gml:Dictionary content model adds a list of gml:dictionaryEntry properties that contain or reference gml:Definition objects. A database handle (gml:id attribute) is required, in order that this collection may be referred to. The standard gml:identifier, gml:description, gml:descriptionReference and gml:name properties are available to reference or contain more information about this dictionary. The gml:description and gml:descriptionReference property elements may be used for a description of this dictionary. The derived gml:name element may be used for the name(s) of this dictionary. for remote definiton references gml:dictionaryEntry shall be used. If a Definition object contained within a Dictionary uses the descriptionReference property to refer to a remote definition, then this enables the inclusion of a remote definition in a local dictionary, giving a handle and identifier in the context of the local dictionary.
The attribute gml:id supports provision of a handle for the XML element representing a GML Object. Its use is mandatory for all GML objects. It is of XML type ID, so is constrained to be unique in the XML document within which it occurs.
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<element name="Dictionary" type="gml:DictionaryType" substitutionGroup="gml:Definition"><annotation><documentation>Sets of definitions may be collected into dictionaries or collections. A gml:Dictionary is a non-abstract collection of definitions. The gml:Dictionary content model adds a list of gml:dictionaryEntry properties that contain or reference gml:Definition objects. A database handle (gml:id attribute) is required, in order that this collection may be referred to. The standard gml:identifier, gml:description, gml:descriptionReference and gml:name properties are available to reference or contain more information about this dictionary. The gml:description and gml:descriptionReference property elements may be used for a description of this dictionary. The derived gml:name element may be used for the name(s) of this dictionary. for remote definiton references gml:dictionaryEntry shall be used. If a Definition object contained within a Dictionary uses the descriptionReference property to refer to a remote definition, then this enables the inclusion of a remote definition in a local dictionary, giving a handle and identifier in the context of the local dictionary.</documentation></annotation></element>