Dear Paola, (01)
> > MW: Entity (types) are the types of things you wish to hold data
> > about. These can be as much verb based - actions, as noun based. So
> > most companies would wish to hold data about the sales they
> made, for
> > example.
>
> I think its considered good practice. Similar arguments would be
> applicable to RDF, imho
>
> Some references quoted below (02)
MW: For an alternative view try:
Developing High Quality Data Models:
http://www.matthew-west.org.uk/Documents/princ03.pdf (03)
Regards (04)
Matthew West
Reference Data Architecture and Standards Manager
Shell International Petroleum Company Limited
Registered in England and Wales
Registered number: 621148
Registered office: Shell Centre, London SE1 7NA, United Kingdom (05)
Tel: +44 20 7934 4490 Mobile: +44 7796 336538
Email: matthew.west@xxxxxxxxx
http://www.shell.com
http://www.matthew-west.org.uk/ (06)
>
> [PS]
> Heuristics-based entity-relationship modelling through natural ...
> File Format: Adobe PostScript - View as Text
> generation of Entity-Relationship (ER) diagrams for database modelling
> from a ..... part of speech such as noun, verb and determiner to
> reflect the word's ...
> www.infm.ulst.ac.uk/~paul/pubs/omaraics04.ps - Similar pages
> - Note this
>
>
> >
> 2.1 Overview of Data Modelling
> The first step in designing a database application is to understand
> what information
> the database must store. This step is known as requirements analysis.
> The information
> gathered in this step is used to develop a high-level description of
> the data to be stored
> in the database. This step is referred to as conceptual design, and it
> is often carried out
> using the ER model. ER models are built around the basic
> concepts of entities,
> attributes, relationships and cardinality. An entity is an object that
> exists in the real
> world and is distinguishable from other objects. These are typically
> derived from
> nouns. Examples of entities include the following: a "student", an
> "employee" and a
> "book". A collection of similar entities is called an entity set. An
> entity is described
> using a set of attributes. The attributes of an entity reflect the
> level of detail at which
> we wish to represent information about entities. Attributes
> may be derived from
> adjectives and adverbs. For example, the "Student" entity set may have
> "ID_number",
> "Name", "Address", "Course" and "Year" as its attributes. A
> relationship is an
> association among two or more entities. Relationships can be typically
> derived from
> verbs. For example, we may have a relationship from this
> sentence: A student may
> "take" many courses. "take" implies a relationship between the entity
> "student" and
> "course". Cardinality represents the key constraint in a relationship.
> In the previous
> example, the cardinality is said to be many-to-many, to indicate that
> a student can
> take many courses and a course can be taken by many students. In an ER
> diagram, an
> entity is normally represented by a rectangle. An ellipse usually
> represents an attribute
> meanwhile a diamond shape shows a relationship. Cardinality is
> represented by 1 for
> the one-sided and M for the many-sided.
>
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