mis 3140 midterm review ch 4 quiz

An entitiy is said to be ________ if it can exist in the databse only when it is associated with another related entitiy occurrence. a.existence-dependent b.existence-independent c.strong d.weak

A - existence dependence

a ________ attribute is one that cannot be subdivided. a.composite b.simple c.single-valued d.multivalued

B - simple

the crow's foot symbol with two parallel lines indicates ____ cardinality. a.(0,N) b.(1,N) c.(1,1) d.(0,1)

C 1:1

the set of possible values for an attribute is a _____. a. domain b. range c. set d. key

a - domain

Attributes have a domain that specifies the data type of the attribute. (t/f)

false

Derived attributes are stored in a special database table. (t/f)

false

an entitiy-relationship model (ERM) is dependent on the database type. (t/f)

false

relationships operate only in one direction. (t/f)

false

the DBMS can easily handle multivalued attributes. (t/f)

false

Ideally, a primary key is composed of several attributes. (t/f)

false Ideally, a primary key in a relational database is typically composed of a single attribute (column).

Cardinality expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity. (t/f)

true

Connectivities and cardinalities are established by buisness rules. (t/f)

true

The ER model refers to a specific table row as an entity occurrence. (t/f)

true

a composite identifier is a primary key composed of more than one attribute. (t/f)

true

the ER diagram represnets the conceptual databse as viewed by the end user. (t/f)

true