NodePropertyExistenceConstraint = (C,O,N,S,T,R,A,I,N,T), SP, (O,N), [SP], '(', Variable, NodeLabel, ')', [SP], (A,S,S,E,R,T), SP, (E,X,I,S,T,S), [SP], '(', PropertyExpression, ')' ;
Variable = SymbolicName ;
NodeLabel = ':', [SP], LabelName ;
LabelName = SchemaName ;