Database handle for the object. It is of XML type ID, so is constrained to beunique in the XML document within which it occurs. An external identifier for the object inthe form of a URI may be constructed using standard XML and XPointer methods. This is doneby concatenating the URI for the document, a fragment separator, and the value of the idattribute.
<element name="AbstractGeometricPrimitive" type="gml:AbstractGeometricPrimitiveType" abstract="true" substitutionGroup="gml:AbstractGeometry"><annotation><documentation>The AbstractGeometricPrimitive element is the abstract head of the substitution group for all (pre- and user-defined) geometric primitives.</documentation></annotation></element>