Standardized logical schema

Definition

The standardization of a relational database conceptual diagram is generally based on only the first three Normal Forms (NF).

The first three NF have the following definition:

· (1NF) An association is called standardized, or in first normal form, if and only if each of the domains concerned in the association contains only atomic elements.

· (2NF) The association must be in 1 NF and ensure for its primary key total functional dependency of each of its non-key attributes (an fd is called total of A in comparison to B, if no part of B - if B is composed! - is sufficient to maintain the fd).

· (3NF) The association must be in 2NF and ensure with regard to its primary key, a direct functional dependency (i.e. non transitive) of each of its non key attributes.

Standardization

Objecteering SQL Designer checks that the first normal form is respected. Indeed, "Set of..." attributes are not accepted.

The user must respect the 2 and 3 normal forms when annotating with the {primaryKey} tagged value.