Identification of objects and identification of relationships between objects

[vldm10]

In my paper "Some Ideas about a New Data Model" set up on the Internet and on this user group on September 17, 2005, I have introduced the
identification of objects and the identification of the relationships
between the objects. These identifiers are defined in Section 1 in this
mentioned paper.

This means I do not use "keys" in database theory, I use identifiers. This
further means that I am introducing a new theory that enables the
identification of objects in the real world and also the identification of
abstract objects that are written in a "memory". This my theory that uses
the identification of real and abstract objects is different from the theory
that uses the keys. One of the consequences of this theory is that the
identifier is always simple. This means that the identifier can always be
taken as a kind of "simple key".

Below is just the beginning of my first paper, published on September 17,
2005, on my website and on the user group: comp.databases.theory.
My key is defined below. I use the term "key" and "identifier" at the same
time.
However, the difference between "key" and "identifier" is big. The
identifier belongs to one theory, the key to another theory. I use these two
terms alternately to make the reader understand this change of concept more
easily.

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Some ideas about a new Data Model
Vladimir Odrljin
New York City, NY USA
Email: vld...@yahoo.com
Posted: September 17, 2005

1. Ordered pair (Conceptual Model, Logical Model)
A Conceptual Model is a domain in which a part of the Real World associated
with subject knowledge is represented.
This model, aside from Entities, Relationship, Attributes and Attributes’
values, has Events.
There are only two kinds of events in the Real World:
i) An event which causes new information
ii) An event which causes some existing information to not be valid after
this event. We will also say this event closes information.
Here information is the meaning of the event in the Conceptual Model.
A Conceptual Model has events which correspond to events from the Real
World. Here they can have only two values:
N and C, they are abbreviations for “new” and “close”.

1.1 Construction of Conceptual Model
We determine the Conceptual Model so that every entity and every
relationship has only one attribute, all of whose values are distinct. So
this attribute doesn’t have two of the same values. We will call this
attribute the Identifier of the state of an entity or relationship. We will
denote this attribute by the symbol Ack. All other attributes can have
values which are the same for some different members of an entity set or a
relationship set. Besides Ack, every entity has an attribute which is the
Identifier of the entity or can provide identification of the entity. This
Identifier has one value for all the states of one entity or relationship.
Like the Logical Model, here we will use the Relational Model, although the
above is not limited to the Relational Model.
An entity set and a relational set are mapped into relations of the Relation
Model. Attributes from an entity or relationship are mapped to the
relation’s attributes. The events from Conceptual Model are mapped to
corresponding “new” and “close” events from the Relational Model.
Let’s denote by Ark the attribute in relation R which corresponds to the
Ack. All the values of the attribute Ark are unique.

1.2 Definition of key
The key K for relation R is the attribute Ark such that:
1. The key K uniquely determines a tuple in relation R and is the primary
key.
2. One particular value of K provides identification for one state of the
corresponding entity (or the relationship)
3. Two or more of the key’s values from relation R, which are related to one
corresponding entity (relationship), provide better identification and
meaning to the entity (relationship).

This construction of entities and relationships enables corresponding
relations to be almost normalized. We don’t have compound keys, we have only
one candidate key, and generally speaking, all the other values that are not
Ark’s can be repeated any number of times

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My first paper can be found on the web site http://www.dbdesign10.com
My second and third paper can be found on the web site
http://www.dbdesign11.com

Vladimir Odrljin