gml:OperationParameter is the definition of a parameter used by an operation method. Most parameter values are numeric, but other types of parameter values are possible. This complex type is expected to be used or extended for all operation methods, without defining operation-method-specialized element names.
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.
Source
<element name="OperationParameter" type="gml:OperationParameterType" substitutionGroup="gml:AbstractGeneralOperationParameter"><annotation><documentation>gml:OperationParameter is the definition of a parameter used by an operation method. Most parameter values are numeric, but other types of parameter values are possible. This complex type is expected to be used or extended for all operation methods, without defining operation-method-specialized element names.</documentation></annotation></element>