A data model describes the entities, classes or data objects relevant to a domain,
the attributes that are used to describe them, and the relationships among them
to provide a common set of semantics for analysis and implementation
There are several variations of data models:
1/ Conceptual data model: is the least detailed; it is the very first model and the most abstract part of our data modeling process. We use this high-level model to start defining our concept and to communicate with non-technical user groups and business owners.
2/ Logical data model: is an abstraction of the conceptual data model that
incorporates rules of normalization to formally manage the integrity of the
data and relationships. It is associated with the design of a solution
3/ Physical data model: is used by implementation subject matter experts to
describe how a database is physically organized. It addresses concerns like
performance, concurrency, and security. database designers may also add primary keys, foreign keys and constraints to the design.
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