The primary key is indicated in the ER model by underlining the attribute

Primary key can have no value .

In the primary key Value should not change over time

Primary key Can be one or more attributes.

A .......... key is composed of two or more attributes, but it must be
minimal

A property or characteristic of an entity. Often shown as an oval or circle.

are those that consist of a hierarchy of attributes Sub-attributes spring from an attribute

More than one attribute value is denoted, such as multiple phone numbers for a person

Derived Attribute :Both multivalued and composite attribute

Attributed is calculated or otherwise derived from another attribute, such as age from a birthdate

are those drawn from the atomic value domains

A relationship may also have attributes

between the instances of two entity types

among the instances of three entity types

between two instances of one entity type

A binary relationship set is of degree ..

A ternary relationship is a relationship type that involves many to many relationships between two tables

How many instances of one entity will or must be connected to a singleinstance from the other entities.

should be the norm in any relational database design and is found in all relational database
environments

A computer language for storing, manipulating and retrieving data stored in a relational