Chapter 14

In the hierarchical database model, data is organized as an inverted ______.

• graph

• tree

• array

• record

In the network database model, the entities are organized in a ______, in which some entities can be accessed through several paths 

• graph

• tree

• array

• record

In the relational database model, data is organized in ______called relations. 

• two-dimensional array

• two-dimensional table

• two-dimensional record

• None of above

What is the result of difference database operation from 2 relation tables? 

• neither the first relation nor the second

• both of the first relation and the second.

• the first relation but not the second

• the second but not the first 

For each entity set in the E-R diagram, we create a relation (table) in which there are n  columns related to the ____ attributes defined for that set. 

• n-1

• n

• n+1

• 1

The union database operation is taking two relations and creating a new relation. What is a result of this operation? 

• neither the first relation nor the second

• both of the first relation and the second

• the second but not the first 

• the first relation but not the second

A database management system (DBMS) is a combination of _____components 

• 2

• 3

• 4

• 5

A _____is a collection of related, logically coherent, data used by the application programs in an organization. 

• database

• file

• MySQL

• flat-file

In a three-level DBMS architecture, the _______ level determines where data is actually stored on the storage devices.

• external

• conceptual

• internal

• physical

The _______ level of a three-level DBMS architecture defines the logical view of the data

• external

• conceptual

• internal

• physical