ACTUAL Questions and CORRECT
Answers
Cardinality - CORRECT ANSWER- maxima and minima of relationships and attributes.
Attribute maximum - CORRECT ANSWER- greatest number of attribute instances possible
for a single entity instance. Attribute maximum is specified as one or many
Attribute minimum - CORRECT ANSWER- least number of attribute instances possible for
a single entity instance. Attribute minimum is specified as zero or one
Singular attribute - CORRECT ANSWER- each entity instance has at most one attribute
instance
Plural attribute - CORRECT ANSWER- each entity instance can have many attribute
instances.
required attribute - CORRECT ANSWER- In ER modeling, an attribute that must have a
value. In other words, it cannot be left empty.
optional attribute - CORRECT ANSWER- In ER modeling, an attribute that does not require
a value; therefore, it can be left empty.
Unique Attribute - CORRECT ANSWER- attribute whose value is different for each entity
instance
On ER diagrams, a 1 follows the name of a unique attribute
, relationship maximum - CORRECT ANSWER- greatest number of instances of one entity
that can relate to a single instance of another entity
determine maximum for the relationship:
city-iscapitalof-state - CORRECT ANSWER- one-one
determine maximum for the relationship:
Person-Has-Passport - CORRECT ANSWER- one-many
a person can have many passports but a passport can only be for one person
Relationship minimum - CORRECT ANSWER- the least number of instances of one entity
that can relate to a single instance of another entity
A relationship has two minima, one for each of the related entities. Minima are usually specified
as zero or one. On ER diagrams, minima are shown after maxima, in parentheses. Ex: M(1) or
M(0).
Dependent Entity - CORRECT ANSWER- An entity that requires a relationship to another
entity for identification.
dependency relationship - CORRECT ANSWER- a relationship between attributes where
one entity only exists in relation to the other entity
master entity - CORRECT ANSWER- The master entity is the entity that the dependent
entity relies on with dependent entity relationships
independent entity - CORRECT ANSWER- does not depend on any other entity