Relation

Relation is based on Attributes ¬

Primary Key Attribute is an Attribute º

<Each relation has at least one primary key attribute.>

{Input parameters of a function represent its primary keys.}

Dependent Attribute is an Attribute º

<It’s not PK attribute.>

{There can be relations without dependent attributes: tables with all attributes being primary key.}

Relation has a Relation Name ®

Relational Schema is a part of Relation Name ¬

Proper Relation Name is a part of Relation Name ¬

Relation is stored in a Stored Object. Server ®

<All active relations are to be of one server.>

Relation. Application Domain

Relation pertains to an SCM. Application Domain ®

Relation has a Local Name ®

<Relation name is “<relation schema name>.<proper relation name>”.>

Relation has a Full Name º

<Relation full name is “<application domain full name>.<relation local name>”.>

Relation. Relation Type

SQL. Table is a Relation º

Stored Procedure is a Relation º

<A relation cannot be a table and a stored procedure simultaneously.>

Relation. Key

Key consists of an Attribute in a Position

[Attribute º(Attribute Sequence)º Position]

<Positions are unique within each key and are between 1 and positions quantity.>

<All key attributes should pertain to one relation.>

Relation has a Primary Key º

Relation has Foreign Keys ¬

Relation has Alternative Keys ¬

Foreign Key references at a Unique Key ®

<A referencing relation references to a referenced relation. The referencing relation has states containing sequences of values of foreign key which is referencing. The referenced relation has a state which contains sequences of values of unique key which is referenced. Each of the foreign key value sequences should be present in the unique key value sequences within the current relation states.>

Unique Key is a Key º

<The allowable states of the relation contain only unique (within a state) attribute value sequences of each unique key.>

Primary Key is a Unique Key º

<It consists of all primary key attributes of the relation only.>

Alternative Key is a Unique Key º

<A unique key can be either primary or alternative.>

Foreign Key is a Key º

<A key can be either unique or foreign.>

Relation. Attribute

Attribute is an Attribute Field º

<It has no a parent attribute field.>

Not Null Attribute is an Attribute º

<A not null attribute pertains to a relation having a possible state set. Each state of the set should not contain rows with null value of the attribute.>

<Primary key attributes are always not null.>

Nullable Attribute is an Attribute º

<All not not-null attributes are nullable ones.>

<An attribute can be either nullable or not null.>

Relation. Attribute Field

Nested Attribute Field is nested to a Parent Attribute Field ®

Parent Attribute Field is an Attribute Field º

Nested Attribute Field is an Attribute Field º

Elementary Attribute Field is an Attribute Field º

<It has no nested attributes.>

Nested Attribute Field has a Position ®

Attribute Field has a Field Name ®

Attribute Field has a Full Name ®

<Full name is a sequence of field names from root attribute field with a dot.>

Attribute Field pertains to a Relation ®

<It pertains to a relation of its root grandparent attribute.>

Relation. Attribute Field. Tree

Use Tree

Attribute Field is a Tree Node º

Parent Attribute Field is a Parent Node º

Nested Attribute Field is a Child Node º