If you see this and wonder It is a bunch of notes being prepared for a section on semantic modelling on the ER wikipedia page and here it is (the rest of this is unused ranting)
Entity-relationship_model#Semantic modelling
and also
Entity-relationship_model#Cardinalities
input notes
edit
http://til.phil.muni.cz/text/materna_duzi_parmenides.pdf the entity "evening star" is not a set
UML rubbish
editClass is a kind of classifier whose features are attributes and operations. Attributes of a class are represented by instances of Property that are owned by the class. Some of these attributes may represent the navigable ends of binary associations.
association’s name A slash = derived A property string, and ?.... solid triangular arrowhead = last in order of ends, has no general semantic interpretation.
ends A multiplicity, and?... • A property string enclosed in curly braces. The following property strings can be applied to an association end: • {subsets <property-name>} to show that the end is a subset of the property called <property-name>. • {redefines <end-name>} to show that the end redefines the one named <end-name>. • {union} to show that the end is derived by being the union of its subsets. • {ordered} to show that the end represents an ordered set. • {nonunique} to show that the end represents a collection that permits the same element to appear more than once. • {sequence} or {seq} to show that the end represents a sequence (an ordered bag). • If the end is navigable, any property strings that apply to an attribute.
Note that by default an association end represents a set. (Proper subsetting implies that the superset is not empty and that the subset has fewer members.) Subsetting is a relationship in the domain of extensional semantics. Specialization is, in contrast to subsetting, a relationship in the domain of intentional semantics,
the uml specification in section 7 regarding classes and associations uses the term "role" threee times and nver in the sense one would expect when talking of relationships
it talks of ordering of ends ownership of ends subsetting "adornments" without ever actually describing what any of it means
other stuff
editthis is not what socrates, plato or aristotle were talking about
this is exactly what Kent, Abrial and Chen were saying when they said that this is not about reality it is about computer systems exactly not what we should be modelling technology is not what we should model the mapping from models to technology is easy but the models MUST be about reality never about computer systems
if you are making a model about shit then if you are any good as a modeller your model will look like shit
(my consolation to myself while trying to model the hideous monstrous abomination that twisted obfuscated abortion that truely bent thing which is 333 pages of gobbledegook http://www.w3.org/TR/xmlschema11-1/ )
http://www.ltg.ed.ac.uk/~ht/XML_MetaArchitecture.html "In the interests of time, XML 1.0 did not define its own data model" Henry S. Thompson should damn well be ashamed of himself for foisting this rubbish on an unsuspecting world and without doing the proper preparation if he worked for me he would be on an instant final warning
it is possible to build a metamodel of ER modelling using about 7 or 8 entities entity, attribute, relationship, role, unique-identifier (and its components) with a bit of a specialisation of relationship for gen/spec and the 2 types of aggregation whereas the model of possible element combinations for XSD is up to over 50 and i am not quite finished and it is a total mess (see my consolation above)
"... and the Truth will make you free." John 8.32 (AV).
Abrial, J. R., "Data Semantics," J. W. Klimbie & K. L. Koffeman Eds., of "Database Management," North Holland Pub. Co., Amsterdam, 1974, pp 1-60.
Chen, P. P., "The Entity-Relationship Model: Toward a Unified View of Data," ACM Trans. on Database Systems, Vol. 1, No. 1, March 1976, pp. 3-36.
Chen, P. P., "The Entity-Relationship Model - A Basis for the Enterprise view of data," Proc. AFIPS 1977 NCC, Vol. 96, AFIPS Press, Montvale, N. J., pp. 77-84.
Dogac, A. & Chen P. P., "Entity-Relationship Model in the ANSI/SPARC Framework," ERA 1983, pp. 357-374.
Halpin, T. & Morgan, T., "Information Modeling and Relational Databases, Second Edition", Morgan Kaufmann, 2008.
Kent, W. "Data and Reality."
Machin, S. J., "A Proposal for a Carbon Technical Information System at NZAS", report to the Manager, Data Processing Services, NZAS, 09-May-91.
Russell, B., "An Enquiry into Meaning and Truth," 1940.
Sheuermann, P., Schiffner, G. & Weber, H., "Abstraction Capabilities and Invariant Properties Modeling within the Entity-Relationship Approach," Proc. Int. Conf. on ERA, 1980, pp. 121-140.
Smith, J. M. & Smith, D. C. P., "Database abstractions : Aggregation and Generalisation," ACM Transactions on Database Systems Vol. 2, No. 2 (June 1977), pp 105-133.
Spencer, R., Teorey, T. & Hevia E. (Index Technology), "ER Standards Proposal," Proc. Int. Conf. on ERA, 1991 (The Core of Conceptual Modelling), pp. 425-431.