ER Model

A weak entity set in an E-R diagram is an entity set that :

• has a primary key

• is not existence dependent on a dominant entity

• must be part of a one to many relationship set

• must not participate as owner in an identifying relationship with another entity set

The entity relationship set is represented in E-R diagram as

• Double diamonds

• Undivided rectangles

• Dashed lines

• Diamond

The Rectangles divided into two parts represents

• Entity set

• Relationship set

• Attributes of a relationship set

• Primary key

Consider a directed line(->) from the relationship set advisor to both entity sets instructor and student. This indicates _________ cardinality

• One to many

• One to one

• many to many

• many to one

An entity set that does not have sufficient attributes to form a primary key is termed a __________

• Strong entity set

• Variant set

• Weak entity set

• Variable set

For a weak entity set to be meaningful, it must be associated with another entity set, called the

• Identifying set

• Owner set

• Neighbour set

• Strong entity set

If you were collecting and storing information about your music collection, an album would be considered a (or) an

• Relation

• Entity

• Instance

• Attribute

An ________ is a set of entities of the same type that share the same properties, or attributes.

• Entity Set

• Attribute set

• Relationship Set

• Entity Model

The descriptive property possessed by each entity set is _________

• Entity

• Attribute

• Relation

• Model

The attribute name could be structured as an attribute consisting of first name, middle initial, and last name. This type of attribute is called

• Simple attribute

• Composite attribute

• Multivalued attribute

• Derived attribute